Washington, Jan 7 (IANS): Iran will have to commit itself to the 2012 Geneva Communique to take part in the January peace conference on Syria, the White House has said.

The Geneva Communique of last year calls for cessation of violence in Syria where rebels are fighting to oust the regime of Bashar al-Assad. Tehran is the main ally of Damascus.

Iran has said it is ready to play a "constructive" role in the Geneva II conference if invited. The meeting, scheduled Jan 22, is aimed at ending the Syrian conflict.

The purpose of Geneva II is to move forward on the principles laid out in the Geneva Communique, White House spokesperson Jay Carney said Monday.

"Obviously you cannot participate constructively if you do not buy into those principles and publicly say so," he added.

UN Secretary General Ban Ki-moon began sending out invitations to the Geneva II meeting Monday.

Iran is not among the first round of nations on the list, which was approved by the representatives of US and of Russia with UN officials at a meeting held Dec 20.

According to Marie Harf, spokesperson for the State Department, Secretary of State John Kerry will discuss with Russian officials to decide Iran's role in the conference.

Even if Iran is to attend the conference at a lower level, it would need to demonstrate "an interest and a willingness" to play a constructive role in the process, Xinhua quoted Harf as saying.