Iraqi leaders said in a statement Tuesday there was "no need" for US forces that stay beyond year-end to receive immunity from prosecution, a key condition set by Washington for any post-2011 training deal.

The remarks raise questions over whether an oft-discussed American military training mission will be agreed for beyond the end-2011 withdrawal deadline set by a bilateral security pact, and how it will be structured if any deal is put in place.

After a two-hour meeting hosted by President Jalal Talabani, the leaders of Iraq's main political blocs said that they "agreed on the need to train Iraqi forces" and quickly purchase military equipment, according to a statement issued by government spokesman Ali al-Dabbagh.

But "the leaders agreed there is no need to give immunity for trainers."

It added: "Training should be held on Iraqi bases, and it should be organised to ensure that Iraqi forces will be professional."

"These forces should... be able to deter any threat against Iraq's internal and external security and maintain the integrity of its territory, water and skies, and its constitutional democracy."

The statement made no mention of how many trainers would be required, for how long, or for what specific needs.

The US military in Iraq did not immediately comment on the statement, but a US embassy official said it was "reviewing the statement."

The official, who spoke on condition of anonymity, said the embassy would "talk with leaders on what this means specifically in terms of our Strategic Framework Agreement security cooperation, and appreciate the democratic spirit displayed by Iraqi leaders in debating this important subject."

US and Iraqi officials assess that while domestic security forces are largely capable of maintaining internal security, they cannot yet defend the country's borders, its maritime boundaries or its airspace.

Late last month, Iraq signed an agreement with the US to buy 18 F-16s as part of attempts to build its nascent air force. Prime Minister Nuri al-Maliki said this summer that the country was looking to buy 36 of the jets.

Iraqi political leaders agreed in early August to open talks with Washington over the training mission, but little visible progress has been made since.

That announcement to hold negotiations came shortly after Admiral Michael Mullen, then chairman of the US joint chiefs of staff, told reporters in Baghdad that any deal would require parliamentary approval stating that US soldiers stationed in Iraq would enjoy immunity from prosecution.

Approximately 43,500 US troops remain in Iraq, and all of them must withdraw by the end of the year under the bilateral security pact, which remains in force if no post-2011 deal is agreed.

Iraq's top military officer, Lieutenant General Babaker Zebari, has repeatedly said that his forces will require training for another decade before they are fully capable of securing the country.