By Jim Muir
BBC News, Baghdad
The UN mandate allowing US troops in Iraq expires at the end of 2008
US presidential contender Barack Obama has repeatedly seized on statements attributed to Iraqi leaders to support his call for a troop withdrawal deadline.
The key statement cited by Mr Obama and others was made by Iraqi Prime Minister Nouri Maliki last Monday in his address to Arab ambassadors in the United Arab Emirates.
The prime minister was widely quoted as saying that in the negotiations with the Americans on a Status of Forces Agreement to regulate the US troop presence from next year, "the direction is towards either a memorandum of understanding on their evacuation, or a memorandum of understanding on a timetable for their withdrawal".
That was the version of Mr Maliki's remarks put out in writing by his office in Baghdad.
It was widely circulated by the news media, and caught much attention, including that of Mr Obama.
There is only one problem. It is not what Mr Maliki actually said.
In an audio recording of his remarks, heard by the BBC, the prime minister did not use the word "withdrawal".
What he actually said was: "The direction is towards either a memorandum of understanding on their evacuation, or a memorandum of understanding on programming their presence."
Mr Maliki is under pressure to reject any infringement on Iraqi sovereignty
Mr Maliki's own office had inserted the word "withdrawal" in the written version, replacing the word "presence".
Contacted by the BBC, the prime minister's office had no explanation for the apparent contradiction. An official suggested the written version remained the authoritative one, although it is not what Mr Maliki said.
The impression of a hardening Iraqi government line was reinforced the following day by comments from the National Security Adviser, Muwaffaq al-Rubaie.
He was quoted as saying that Iraq would not accept any agreement which did not specify a deadline for a full withdrawal of US troops.
Significantly, Mr Rubaie was speaking immediately after a meeting with the senior Shiite clerical eminence, Ayatollah Ali Sistani.
But in subsequent remarks, Mr Rubaie rode back from a straightforward demand for a withdrawal deadline.
He said the talks were focused on agreeing on "timeline horizons, not specific dates", and said that withdrawal timings would depend on the readiness of the Iraqi security forces.
The confusion reflects the dilemma facing Iraqi government leaders.
Troop withdrawal has become a major issue in the US election campaign
On the one hand, many of them - particularly among the Shia factions - face a public which regards the US presence as a problem rather than a solution.
With provincial elections coming up soon, they could be outflanked by more militant elements such as the supporters of cleric Moqtada Sadr, who wants American forces out now and opposes negotiations that would cover their continued presence.
Yet the government knows that its own forces are not yet in a position to stand on their own against the two major challenges they face - the Sunni radicals of al-Qaeda and related groups, and the militant Shia militias which were partly suppressed in fierce battles this spring in Basra and Baghdad.
Both groups could simply bide their time awaiting the American withdrawal before making a comeback drive.
Violence has fallen off considerably from the horrendous levels of 2006 and the first half of 2007, but hundreds of people are still dying violent deaths every month.
Hence the ambiguity in statements by Iraqi leaders, who know that their own survival depends on US support continuing until Iraqi forces are genuinely able to stand alone.
The indications are that the talks are now focusing not on deadlines for a complete withdrawal - but on phasing US troops out of Iraqi cities, and into a role providing logistical backing, firepower and air support, with a reduction of front-line troops.
"On substantive issues, there's not much daylight between the two sides," said a US official close to the troop talks with the Iraqi government.
"The troops will leave when the Iraqis are ready to take over. But they [Iraqi leaders] need to get what they need, and to get cover for it.
It is politics - how you package it, how you sell it to your people. They want our support, but they also want to show that there's progress towards sovereignty."
What the Iraqis see as issues of sovereignty have been a sticking-point in the talks, especially such items as a US demand for operational freedom and immunity from prosecution for US troops.
Officials admit that the negotiations are in a state of flux, and that the Status of Forces Agreement, which was to have been concluded this month, may end up being a simple protocol or memorandum of understanding giving some sort of legal basis for a continued US presence after the current UN mandate expires at the end of the year.
The issue has become highly politicised on both sides.
Iraqi leaders will no doubt continue to make ambiguous statements. And US presidential contenders will no doubt continue to construe them to their own advantage.
But when Mr Obama visits Baghdad, as he is expected to later this month, he is unlikely to find that the Iraqi government is quite as set on demanding deadlines for US withdrawal as he would like to think.