Iraqi Prime Minister Nouri al-Maliki has accelerated his country's rearmament program with multibillion-dollar contracts with the United States, Russia and Czech Republic in the last two weeks.

It's not altogether clear why the Iraqis, flush with revenues from high oil prices, are scrambling to buy up so many weapons systems all at once.

The Iraqis say they need combat jets and air-defense systems to protect their air space and borders, which are poorly guarded since U.S. forces completed with withdrawal from Iraq in December 2011.

But the spread of Maliki's military purchases is likely to be causing some concern in Washington less than a year after the United States wrapped up its military withdrawal from Iraq, as well as complicate the already complex and worrying geopolitical situation in the region.

The Iraqi government signed a deal to buy 18 Lockheed Martin F-16IQ Block 52 fighter jets, worth some $2.3 billion, Thursday.

It bought another 18 in 2011 for around $4.3 billion. First buys of new weapons systems usually cost more than subsequent contracts.

These buys are enough to equip the first two fighter squadrons of the nascent Iraqi air force now being reconstituted, so far without any combat arm.

Acting Defense Minister Sadoun al-Dulaimi said Baghdad's also discussing the purchase of Boeing AH-64 Apache attack helicopters and unspecified air-defense missile systems, contracts that will run into billions of dollars for U.S. defense companies.

The U.S. still remains Iraq's leading arms supplier with $6 billion is sales already sealed, with deals possibly worth another $12 billion under discussion.

Thursday's deal came 10 days after Maliki closed a $4.2 billion arms deal with Russia during a visit to Moscow for 30 Mil Mi-28 attack helicopters and 42 Pantsir S-1 air-defense missile units.

A joint communique at the end of Maliki's Moscow visit said talks are under way for the purchase of an unspecified number of MiG-29 interceptor jets, heavy armored vehicles and other weapons systems.

Negotiations for the Oct. 9 arms package took five months, Iraqi sources said. But it seems to have caught the Americans on the hop.

So did an Oct. 12 contract with the Czech Republic for 24 Aero-Vodochody L-159 sub-sonic advanced trainer jets worth about $1 billion. These can also be used as light-attack aircraft, ideal for counter-insurgency operations.

Maliki's shift toward Russia and Eastern Europe for sophisticated arms may indicate a growing impatience and frustration with the Americans, who have refused to sell Iraq advanced weapons, particularly air-to-air and air-to-ground missiles, with the F-16s.

This is largely to soothe the concerns of Iraq's neighbors and the country's Kurdish minority who all suffered grievously during Saddam Hussein's rule that ended in 2003.

But Maliki's currently feuding with Iraq's semi-autonomous Kurds and the Sunni minority that was the backbone of Saddam's regime, while he eliminates political rivals of his Shiite-dominated government and consolidates his power, particularly through controlling the military and security forces.

Many Iraqis, and Sunni neighbors like Saudi Arabia, see all this as a new dictatorship in the making at a time when U.S. influence in the region if ebbing after four decades.

Maliki, a Shiite who has long had close relations with Shiite-dominated Iran, has been urging the Pentagon to speed up delivery of the first batch of F-16s.

These were supposed to begin in 2014. But Maliki told U.S. Deputy Secretary of Defense Ashton Carter, who showed up in Baghdad after the Russian deal was announced, he wants deliveries to start in 2013.

It would seem Maliki's turn to Russia got Washington's attention.

"Does this mean Iraq is on a course of strategic defiance of the United States"? mused veteran analyst M.K. Bhadrakumar, a former Indian ambassador with wide experience in the region.

"What needs to be factored in is that the U.S. still remains Iraq's No. 1 arms supplier...

"A strategic defiance of the United States is far from Maliki's thoughts -- at least, for now.

"Maliki's message needs to be taken more as of one of assertively stating that Iraq is an independent country," Bhadrakumar observed.

"Arguably, it's not very different from the thrust of Egypt's policies under President Mohammed Morsi.

"Simply put, the U.S. needs to come to terms with such happenings as Maliki's decision to revive military ties with Russia or Morsi's decision to pay his first state visit to China."