Hazim Shaalan said on Monday that the interim government had already sought help from Egypt and Arabian Gulf nations to encourage Sunni participation.
"And if such participation requires a delay to the election date, they could be delayed," he said.
Asked if the US would accept such a delay, Shaalan said he was convinced "Washington would be happy that the election operation was comprehensive with the participation of all".
He pointed out that a boycott of the election by Iraq's Sunni political forces would mean that "around one half of [Iraqi] society would be absent from this election and the citizens of Ramadi, Mosul, Tikrit and Diala would not take part".
Iraq's main Sunni Muslim political movement, the Iraqi
Islamic Party, has announced its intention to boycott the landmark vote.
Sunni groups say voting is not
viable due to a lack of security
The effect may be that Iraq's Shia overturn decades of Sunni-dominated rule in the vote.
But not all Shia groups intend to take part in the elections either, although Shaalan has raised the possibility of holding talks with boycotting Shia movements such as that of Muqtada al-Sadr, saying it was "possible to have a dialogue with them".
Iraqis are to vote for a 275-member national assembly that would draft a constitution to replace the country's interim law passed by the now defunct US-led occupation authority, ahead of fresh elections.
In the first reaction to Shaalan's poll delay offer, Iyad al-Samarrai, assistant general-secretary of the Iraqi Islamic Party, told Aljazeera that such an initiative - presented in the form of a speech - was inadequate.
"Our position is clear - we have spelled out that the administrative and organisational procedures [currently in place] are inadequate and that political and security situations are not encouraging," he said.
He said his party delivered several initiatives concerning the election to the interim government, but they were all ignored.