Tony Blair was one of Britain's most successful prime ministers but his support for the 2003 war in Iraq has overshadowed his achievements in office and his subsequent career as globe-trotting elder statesman.

The former Labour leader is expected to be severely criticised by the official inquiry into Britain's role in the conflict and subsequent occupation, which will finally be published on Wednesday after seven years.

Blair persuaded his cabinet and parliament, many of whom were strongly opposed, to back the US-led invasion on the basis of intelligence about Iraq's biological, nuclear and chemical weapons.

The weapons were never found.

In his decade in office, during which he was elected thrice, Blair oversaw a period of prosperity, secured peace in Northern Ireland and hugely expanded gay rights.

But nine years after leaving Downing Street, he remains reviled by many of his countrymen for a conflict that most now consider misguided -- and some see as a war crime.

His critics in parliament were already lining up against him ahead of the inquiry report, examining the possibility of legal action and even a retrospective impeachment.

Last year, he apologised for the wrong intelligence and for some of the mistakes in planning, but said he did not regret removing Saddam Hussein.

- Reinventing Labour -

The current Labour leadership has broken with Blair's pro-market policies, but there is no denying the transformation he had on a party that in 1983, when he was first elected to parliament, was in disarray.

Working closely with Gordon Brown, his future finance minister, Blair ditched the party's commitment to nationalisation of industry and rebranded it as the centrist "New Labour".

In 1997 he was elected with a landslide, at 43 becoming Britain's youngest premier since 1812, and ushered in a new era of hope and confidence for the nation after 18 years of Conservative governments.

The following year brought a peace deal in Northern Ireland, the British province devastated by three decades of violence between Protestant and Catholic communities.

With the economy booming, increases in spending on health and education helped secure another election win in 2001.

After the September 11, 2001 attacks, Blair was quick to ally Britain with US president George W. Bush.

London sent troops to Afghanistan, and in 2003, agreed to join the US-led mission to remove Saddam Hussein in Iraq.

But a million people protested on the streets of London against the Iraq invasion, and when the evidence for the war proved flawed, wider dissatisfaction set in.

Blair won the election in 2005, a record third term for a Labour premier, but any jubilation was short-lived.

On July 7, 2005, the day after London won the right to host the 2012 Olympic Games, four British suicide bombers attacked the capital's public transport system, killing 52 people.

Two years later Blair stood down, finally conceding defeat in a long and increasingly bitter power play with Brown, who insisted it was his turn to wear the crown.

- Diplomacy, philanthropy, consultancy -

Blair has spent most of the last decade abroad, including eight years working part-time as the unpaid envoy for the diplomatic Middle East Quartet, comprising the United Nations, United States, European Union and Russia.

His remit was to support the Palestinian economy and institutions in preparation for eventual statehood, but he stepped down last year after failing to produce a meaningful breakthrough.

The controversy over Iraq has not stopped him advocating military action elsewhere, urging Britain and its Western allies to commit ground forces in the fight against the Islamic State group.

Blair made a rare foray back into British politics to warn of the dangers of leaving the European Union in the June 23 referendum -- an intervention that fell on deaf ears.

A committed Christian who converted to Roman Catholicism after leaving office, Blair set up a foundation to support inter-faith dialogue and counter extremism, and has also worked with governments in developing nations in Africa.

Balancing out his philanthropic endeavours have been a number of lucrative advisory roles, including with the government of Kazakhstan.

His personal income reached tens millions of pounds, a fact that is also routinely held against him in the British press.

Blair in spotlight as UK Iraq inquiry gives verdict
London (AFP) July 6, 2016 - The official inquiry into Britain's role in the Iraq war finally reports on Wednesday, seven years after it launched, with former prime minister Tony Blair expected to face severe criticism.

Relatives of some of the 179 British troops who died will gather in London for the publication of the Chilcot report, which runs to 2.6 million words -- more than four times the length of "War and Peace".

The inquiry, launched in 2009 as the bulk of British troops withdrew from Iraq, was tasked with investigating the run-up to the 2003 US-led invasion and the subsequent occupation.

Anti-war protesters are converging on the conference centre near the Houses of Parliament where civil servant John Chilcot will present his report, to repeat their calls for Blair to be prosecuted for war crimes.

Tens of thousands of Iraqis died during the conflict and the sectarian war that followed. The country remains plagued by violence, seen most recently in Sunday's car bomb in Baghdad that killed more than 200 people.

The US-led invasion was deeply controversial at the time as it did not have explicit approval from the UN Security Council, while claims that Iraqi leader Saddam Hussein had weapons of mass destruction proved unfounded.

Chilcot was not asked to rule on the legality of the invasion, but leaks suggest Blair will be heavily criticised over the decision-making process.

His critics are already lining up against him, with former Scottish first minister Alex Salmond gathering cross-party support to bring legal action or symbolically impeach him.

Blair apologised last year for the fact the intelligence was wrong, and for mistakes in the planning, but said he did not regret removing Saddam Hussein.

"We haven't set out to criticise individuals or institutions," Chilcot said ahead of the report launch at 1000 GMT.

"However, I made very clear right at the start of the inquiry that if we came across decisions or behaviour which deserved criticism then we wouldn't shy away from making it."

- 'Get at people' -

More than 120 witnesses gave evidence during months of public hearings, including Blair, his successor Gordon Brown, spy and military chiefs and ministers.

The inquiry panel -- one of whom has since died -- trawled through 150,000 government documents, in an investigation Chilcot said was on "an unprecedented scale".

Their report was delayed by wrangling over what could be published, from diplomatic notes to records of cabinet meetings, as well as the need to give key figures prior warning.

Among the documents to be published are reportedly 29 letters sent by Blair to US president George W. Bush, and some record of conversations between the pair.

Bereaved relatives had pressed for the inquiry amid criticism of the planning and management of the conflict, and accusations that the troops were not properly equipped.

Lawyers for some of them said they would be looking for evidence of neglect of duty or misconduct in public office.

However, other relatives are boycotting the publication, declaring that they already expect it to be a whitewash.

The International Criminal Court, which was petitioned at the time to examine possible evidence of war crimes, has said it will consider the report but has no investigation open.

The legality of the war is outside its jurisdiction.

Admiral Alan West, the head of the Royal Navy when the war began, told The House magazine that he hoped the report would not spark a witchhunt.

"What one really wants out of it is lessons so that we don't make the mistakes again. I have a horrible feeling what other people want is to be able to get at people," he said.

- Labour woes -

The war, which at one point saw 46,000 British troops deployed, mostly in southern Iraq around the strategic oil hub of Basra, still looms large over British politics.

It has led to deep reluctance to commit ground troops elsewhere, notably in Libya and Syria, and still divides Blair's Labour party, which is now in opposition.

Labour leader Jeremy Corbyn is currently facing a rebellion by his own MPs, but is expected to use the report to bolster his position.

The veteran socialist, who was only elected last year, was strongly opposed to the war in Iraq and maintains it was illegal, while many of his critics had supported it.