The US has been concerned that blacklisting the candidates could lead to sectarian tensions and jeopardise the elections.

But speaking at a joint press conference with Jalal Talabani, the Iraqi president, Biden said that he was certain Iraq would find a "just" solution.

Sectarian tensions

"This is for Iraqis to do, not for me," Biden said.

"After today's discussions, though, I am confident that Iraq's leaders are seized with the problem and are working for a final, just solution."

In depth


Iraq's internal dilemma
Election ban troubles candidates

Biden's visit underscores Washington's concerns over the election, which has been seen as an important step in healing Iraq's wartime divides and allowing the US to accelerate its troop withdrawals.

Nasser al-Ani, Iraq's presidential spokesman, said Iraq was willing to listen to suggestions on easing the political standoff caused by the blacklist, but "nobody can interfere in Iraqi affairs ... Biden or others".

Ali al-Dabbagh, a spokesman for the Shia-led government, also drew a clear line on outside views over Iraq's efforts to identify and weed out suspected supporters of the outlawed Baath party, headed by Saddam.

"It is an internal affair that should be discussed by Iraqi political entities,'' he said.

Sunni complaints

The list of banned candidates was drawn up by a panel charged with preventing high-ranking Baathists from returning to public life.

The names included Saleh al-Mutlaq, a popular Sunni politician, which triggered protests from minority Sunnis who complained that majority Shias were trying to marginalise them.

The panel's ruling, which was upheld by Iraq's independent electoral commission, still faces a court challenge.

Talabani said there would be a meeting in the coming days between the presidency, leaders of parliament, heads of the judiciary and al-Maliki to "find a legal and constitutional solution" to the row over the banned candidates.

The incident raised concerns about Iraq's fragile security with the parliamentary election less than seven weeks away.