With Thursday marking the withdrawal from Iraq of the last remaining U.S. combat troops, neighboring countries are jockeying for influence in the war battered country, some experts said.

But it remains unknown how much of a foothold states such as Iran, Saudi Arabia and Turkey -- as well as the United States -- can gain, as Iraq has been known to push back against what it views as foreign meddling in its affairs.

Upon taking office, U.S. President Barack Obama vowed to withdraw U.S. forces and later set an Aug. 31 deadline for U.S. forces to pack up and leave. Fifty-thousand U.S. troops are expected to remain until the end of 2011 and play a non-combat and training roll.

But Iraq's attempts at forming a government have been stalled for months, and ongoing disagreements between Iraqi Prime Minister Nouri al-Maliki and main political rival Iyad Allawi could continue to slow the process.

That makes Iraq vulnerable to bordering nations' attempts to influence the country's politics, some experts said.

Iran, which fought a brutal war with Iraq in the 1980s that saw an estimated 1 million Iranian casualties, has the greatest capacity to influence Iraqi politics right now, some analysts said.

The last thing Iran wants to see is a strong Iraq, and there are enough Shia politicians in Iraq who are close to Tehran and can block the formation of an Iraqi government, wrote global intelligence company Stratfor on its Web site.

Dex Torricke-Barton, a security consultant for the United Nations, said Iran has been attempting to influence Iraq's main Shia factions, such as the supporters of Prime Minister Maliki.

Meanwhile, Saudi Arabia backs the Allawi bloc and Turkey is trying to influence the situation in Northern Kurdistan, he said.

"The goal of many of Iraq's neighbors is to turn the country into a client state," he said, but added that occupation of Iraqi territory is unlikely.

The White House said U.S. Vice President Joe Biden is working closely with Iraqis to establish an Iraqi government, and the administration is keeping a close eye on the matter.

Speaking from Washington Tuesday, outgoing U.S. Ambassador to Iraq Christopher Hill expressed confidence that Iraq would establish a government and said the country is moving in the right direction. Indeed, some argue that no neighboring state will impose its will on Iraq, although foreign influence could deepen as U.S. forces draw down. "Whenever a nationalist issue comes up, the Iraqis push back very hard against external interference," said Joost Hiltermann, the Middle East and North Africa deputy program director at the International Crisis Group.