Baghdad ? A U.S. Embassy official said Democratic presidential contender Barack Obama arrived in Iraq today where he will meet with commanders and troops in a war he has long opposed.

Obama was expected to meet Gen. David Petraeus as well as Iraqi Prime Minister Nouri al-Maliki while in the country, although aides provided few details, citing security concerns.

Obama arrived as part of a congressional delegation that also included Sens. Jack Reed, D-R.I., and Chuck Hagel, R-Neb., following stops in Kuwait and Afghanistan. The delegation met Sunday in Kuwait City with Kuwait’s emir, Sheik Sabah Al Ahmed Al Sabah, and other senior officials, the Kuwait News Agency reported.

All three are longtime critics of the U.S. involvement in the war in Iraq. Obama has called for withdrawing American troops at the rate of one or two brigades per month, and an end to combat operations within 16 months. He has said he favors leaving a residual force in the country to provide security for U.S. personnel, train Iraqis and counter attacks by al-Qaida.

The delegation arrived amid controversy over al-Maliki’s published comments in a German magazine that appeared to endorse Obama’s 16-month timetable. The Iraqi leader’s aides have since said his remarks were misunderstood, and he is not taking sides in the U.S. election.

Obama’s trip occurred less than four months before the presidential election. It is Obama’s second trip to Iraq, but conditions are quite different from when he visited in January 2006. Obama’s first tour was treated as a footnote, while the country was caught in a growing Sunni insurgency and was moving toward a flood of sectarian violence. But the bloodshed has declined significantly since Bush sent thousands more troops last year to help quell the rising violence.

Sen. John McCain has been critical of Obama’s position on Iraq, saying the decision to pull out should be determined by progress, not a timetable.

The presumed Republican candidate supports the war, and has been critical of some aspects of its handling. But he was a vocal supporter of the decision to send in more troops.

McCain’s foreign policy adviser, Randy Scheunemann, said Obama “is stubbornly adhering to an unconditional withdrawal that places politics above the advice of our military commanders, the success of our troops, and the security of the American people.”

“Barack Obama is wrong to advocate withdrawal at any cost just as he was wrong to oppose the surge that has put victory within reach,” Scheunemann said in a statement.

U.S. commanders have begun withdrawing some of those additional troops and Obama argues they should be sent to Afghanistan, which he says is the “central front” in the fight against terrorism, to reinforce efforts there against a resurgent Taliban and to control spiraling violence.

McCain also supports sending troop reinforcements to Afghanistan.

“There’s starting to be a growing consensus that it’s time for us to withdraw some of our combat troops out of Iraq, deploy them here in Afghanistan, and I think we have to seize that opportunity. Now is the time for us to do it,” Obama said in a CBS News interview broadcast Sunday after a two-hour meeting with Afghan President Hamid Karzai.