MOSCOW/GENEVA (Reuters) - The United Nations said on Wednesday no date had been set for the next round of Syria peace talks, contradicting a report quoting Russia's deputy foreign minister as saying talks would resume in Geneva on May 10.
U.N. Special Envoy Staffan de Mistura is struggling to keep the peace process alive after the main opposition High Negotiations Committee (HNC) left formal talks last week.
The HNC said on Wednesday that it was up to the United Nations to say when peace talks would resume, but that it would not take part until its demands were met.
Russian Deputy Foreign Minister Mikhail Bogdanov's comments were reported but RIA news agency on Wednesday, but a spokeswoman for de Mistura said in an email that May 10 was speculation.
Later, HNC chief coordinator Riad Hijab, a former prime minister, called in a statement for an extraordinary meeting in Paris of the "Friends of Syria" group of countries in order to contain the worsening violence and grave humanitarian situation on the ground.
A meeting of the group - which excludes Russia - should aim to "put an end to the hostilities against the Syrian people and put pressure on the regime and its allies to abide by the international resolutions and put an end to their severe violations against the Syrian people", the statement said.
De Mistura was due to address the U.N. Security Council by video-link on Wednesday night from Geneva at the end of a two-week round which began on April 13.
He is expected to speak beforehand with both U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov, the co-sponsors of the fragile two-month ceasefire who are steering the talks.
"With the whole thing falling apart, it is going to require some high-level inspiration to get it started again," a Western diplomat told Reuters.
De Mistura is talking about May 14-15 for starting the next round, a second Western diplomat said.
"But it is very, very theoretical," that diplomat said. "It is not at all a given that the two parties will return to Geneva. De Mistura feels that ending the round without giving a date for the next one would not be a good sign."
The Syrian government said on Tuesday it had held a final session of talks with de Mistura in a "useful and constructive round", but diplomats warned that an escalation of fighting around Aleppo threatened the shaky peace process.
George Sabra of the HNC said on Wednesday his group would not attend talks unless the situation on the ground improved.
"All the while real steps aren't taken on the ground in Syria, the participation of the delegation of the HNC will remain suspended," Sabra said.
Russian Foreign Ministry spokeswoman Maria Zakharova said on Wednesday that the HNC's conduct was "worrying" and that the group had failed to make constructive proposals at the talks.
De Mistura still aims to convene a ministerial meeting of major and regional powers under the International Syria Support Group (ISSG), before the next round is held, the second Western diplomat said.
This would probably be next week, although Russia was not yet on board, he said.
(Reporting by Andrew Osborn in MOSCOW, Stephanie Nebehay and Shadia Nasralla in GENEVA and Tom Perry in BEIRUT; Writing by Dmitry Solovyov; Editing by Raissa Kasolowsky)