The Iraqi parliamentary coalition Building, or al-Binaa in Arabic, has accused Iraqi President Barham Salih of perjury and violation of the constitution after Salih refused to appoint the coalition's candidate as the prime minister-designate.

A statement by the coalition, headed by Hadi al-Ameri, said "we were surprised that the president insisted on violating the constitution and not appointing the candidate of the largest coalition under the pretext of rejecting the candidate from some political parties."

The coalition "called on the parliament to take the legal measures against Salih over perjury and violation of the constitution," according to the statement.

Earlier in the day, Salih sent a letter to Parliament Speaker Mohammed al-Halbousi, rejecting the nomination of Asad al-Eidani by the Building coalition as the largest coalition formed by some winning blocs after the 2018 parliamentary elections.

In the letter, published by some local media, Salih said his position on the current nomination "may be considered a violation of the constitutional text," so he was ready to resign from the post of the president.

Salih also said the nomination of al-Eidani was not welcomed by the protesters.

Political and parliamentary moves must always reflect the public will, meet the requirements of social security and peace, while providing good governance in line with people's aspirations and sacrifices, Salih said in his letter.

Salih's letter came amid a political row over who would be chosen as a new prime minister-designate to form an interim government ahead of early parliament elections.

Mass demonstrations in parts of Iraq led to the resignation of Adel Abdul Mahdi and his government.