US President Barack Obama on Tuesday welcomed Australian Prime Minister Malcolm Turnbull to the White House, saluting Canberra's role in the fight against the Islamic State group.

"We are going to talk about how we can strengthen our cooperation both in Syria and Iraq but also countering violent extremism globally," Obama said.

The deadly attacks on Thursday in Jakarta that were claimed by the IS group shows that Southeast Asia is "an area we have to pay attention to and watch."

Australia, with six fighter jets deployed, takes part in US-led air strikes against IS targets, and is heavily involved in training Iraqi security forces.

Last week, Australian Defense Minister Marise Payne rebuffed a US request for a larger military commitment, saying its contributions to the anti-IS fight were already "substantial."

But she said Australia would offer more transport aircraft for humanitarian missions.

Stressing their "strong and steadfast" alliance, Obama also highlighted the role of the two countries as the "driving force" in the Trans-Pacific Partnership, a vast free trade zone encompassing 12 Pacific Rim countries, but not China.

"It is going to be good for our economy, for our workers and our businesses," he said.

"For us to thrive in the 21st century, it's important for us to be making the rules in this region and that's exactly what TPP does," he said.

Turnbull, who was making his first visit to Washington since taking office in September, noted his "very productive" discussions with US Defense Secretary Ashton Carter, adding that the US-Australian partnership in Iraq and Afghanistan is "very, very strong."

"We have to constantly lift our game in the way we engage with and tackle these extremists, particularly ISIL -- but there are many others -- as they operate in the cyber sphere," he said, using an alternate acronym for IS.

"And so I'm pleased that we're going to be working on even closer collaboration there," he said.

On TTP, Turnbull said it was lifting the standards for a rule-based international order, and adding to its security by integrating the region's economies.