Sunni Arab MPs have been calling on al-Yawir to refuse the post, offered to him by a Kurdish and Shia bloc who between them have the two-third majority needed to form a government, saying it would signal the marginalisation of their once politically dominant sect.
"The president has declined the nomination. He does not wish to say why at present," an official in al-Yawir's office said on Monday.
Al-Yawir has said Sunnis, who won only 17 of the 275 parliamentary seats after largely boycotting the 30 January
elections, must retain the presidency to help stabilise the country and ensure their involvement in the political process.
The presidency could still go to another Sunni candidate, Fawaz al-Jarba, a general in the former Iraqi army. But al-Jarba is among the few Sunnis on the Shia list which won the election and which many Sunnis are wary of.