President Barack Obama declared Monday that the Iraq war was nearing an end "as promised and on schedule," touting what he called a success of his administration though it comes amid persistent instability and uncertainty in Iraq.

Obama cited progress toward meeting his deadline of withdrawing all U.S. combat troops from Iraq by the end of this month. A transitional force of 50,000 troops will remain to train Iraqi security forces, conduct counterterrorism operations and provide security for ongoing U.S. civilian efforts. Under an agreement negotiated in 2008 with the Iraqis, all American troops are to be gone from Iraq by the end of next year.

"The hard truth is we have not seen the end of American sacrifice in Iraq," Obama said in a speech to the national convention of the Disabled American Veterans. "But make no mistake, our commitment in Iraq is changing -- from a military effort led by our troops to a civilian effort led by our diplomats."

The main message of Obama's appearance was the move toward fulfillment of Obama's campaign promise to end the Iraq war, a position that perhaps most defined his 2008 candidacy and was key to his base of support in the liberal wing of his party. With pivotal congressional elections approaching, the White House wants to highlight the progress as a success story. Monday's speech was only the first in a series of such events planned for this month, with others to be headlined by the president as well as Vice President Joe Biden and other administration officials.

"The message is, when the president makes a commitment, he keeps it," White House spokesman Bill Burton told reporters traveling with Obama to Georgia on Air Force One.

But the rhetoric comes amid deep concerns about Iraq's stability.

U.S. officials have stepped up the pressure on Iraqi leaders to overcome a five-month political impasse that has prevented the formation of a new government following elections earlier this year.

In a reminder of Iraq's fragility, two bombings and a drive-by shooting killed eight people there Monday.

With such attacks remaining a daily occurrence, especially in Baghdad, and government figures showing July to be the deadliest month for Iraqis in more than two years, questions persist about the readiness of Iraqi security forces to take over for the Americans.