World powers will meet in Geneva on Saturday in an attempt to find ways of ending the violence in Syria, senior diplomats at the United Nations have said.
US secretary of state Hillary Clinton and Russian foreign minister Sergey Lavrov will be joined by other senior diplomats from the UN Security Council nations and possibly neighbours of Syria, the diplomats said.
UN officials said they are preparing to send out invitations and expect to make an announcement later.
Russia and the United States have both said they want to help UN-Arab League envoy Kofi Annan as he tries to revive a six-point peace plan for Syria, but Russia and China, two of the Security Council's five permanent members, have twice shielded Syria from UN sanctions over a crackdown on the uprising against president Bashar Assad's regime.
Separately, UN secretary general Ban Ki-moon and a panel of UN human rights investigators headed by Brazilian professor and diplomat Paulo Sergio Pinheiro are due to report to the UN's Human Rights Council in Geneva.
Mr Annan's deputy, Jean-Marie Guehenno, a former UN peacekeeping chief, and UN high commissioner for human rights Navi Pillay will also address the council.
A senior UN official said violence in Syria had "reached or even surpassed" levels seen before the ceasefire agreement of April 12.
Mr Guehenno said the six-point plan forged by Mr Annan "is clearly not being implemented", adding that the Syrian government and rebel groups must be made to understand there are "consequences" to failure to implement the six-point plan.