WASHINGTON (AFP) - The United States warned Thursday that the window on difficult negotiations for a US-Iraq security pact is "rapidly coming to a close" as it reviewed proposed Iraqi changes to the deal. "I really don't want to comment until we've had a chance to really review them," State Department deputy spokesman Robert Wood told reporters when asked about the proposed amendments. "But, you know, as we said, we think we have a good agreement. And the window for any kind of discussions, negotiations is ... rapidly coming to a close," Wood added. "So I'll just leave it at that. Once we have something to say on it, we will," he said. "But for the moment, we're just taking our time in reviewing it to make sure that ... we've got a good sense of what it is the Iraqis have put forward." President George W Bush on Wednesday promised to consider Baghdad's proposed changes but warned against shifts that risked "undermining" the accord. "We received amendments today (Wednesday) from the government. We're analyzing those amendments. We obviously want to be helpful and constructive without undermining basic principles," Bush told reporters. Bush, who did not spell out what sorts of changes to the planned Status of Forces Agreement (SOFA) would be unacceptable, declared he was "very hopeful and confident that the SOFA will get passed." The US president had hoped to have the accord in hand by July 31, but now is all but certain not to see it approved before the November 4 elections to choose his successor. The draft version has drawn fire from Iraqi political figures on grounds that it undermines their war-torn country's sovereignty, likely to be a key theme in local and regional elections set for January 31. Radical Shiite cleric Moqtada al-Sadr opposes the pact, while top Shiite cleric Grand Ayatollah Ali Sistani has warned through a statement from his office that any final deal must not harm Iraqi sovereignty. The Iraqi cabinet has authorized Maliki to negotiate changes in the pact, which will lay out the rights and responsibilities of US forces in Iraq beyond December 2008 when their present UN mandate expires. Meanwhile, Baghdad wants to delete any reference in the draft security pact with Washington to the possibility of US troops staying in Iraq after 2011, an MP close to Prime Minister Nuri al-Maliki told AFP on Thursday. The demand is one of five amendments proposed by Iraq, said Ali al-Adib, a Dawa party member of parliament. "The Iraqi government wants to remove from the agreement any mention of a possible extension of the American presence in Iraq," he said. The draft pact says US forces will withdraw from towns and neighbourhoods by the end of June next year and from the whole country by 2011. In the latest version, clause four of section 25, dealing with the withdrawal of American troops, allows "the possibility for each party to ask the other to put back or bring forward the date of withdrawal." It says any such change must "have the approval of both sides". Concerning immunity for American solidiers, another of the thorny issues of the agreement, Adib said: We want the joint US-Iraqi command and not just American forces to decide whether or not a soldier suspected of crime was on a mission."  Clause nine of section 12 of the most recent version grants immunity from Iraqi law to American soldiers if they were on a mission when the crime was committed. American and Iraqi negotiators have been struggling for months to finalise the text of the SOFA (Status of Forces Agreement). Maliki will submit a revised text to Washington after including the amendments sought by his ministers. US President George W. Bush on Wednesday promised to consider Baghdad's proposed changes but warned against shifts that risked "undermining" the accord.