Ambassador Vitaly Churkin, under fire from Western colleagues for blocking attempts to enforce humanitarian corridors in the war-torn country, said Moscow wanted a political solution.
He told a news conference it would be "fundamentally flawed" to ignore the need for a quick successor to mediator Lakhdar Brahimi, who stepped down Saturday, given the latest collapse in peace talks.
"Who's going to test the waters? Who's going to encourage the parties to make some shift in their positions?" Churkin asked.
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"We believe that, after just two five-day rounds of talks, to say that things are so stalemated that there is no need to continue those negotiations, this is not to us entirely persuasive."
"We hope the (UN) secretary general will find a good person and make the announcement as quickly as possible," he added.
Moscow has four times vetoed Western resolutions on Syria, protecting close ally Damascus and paralyzing Security Council efforts to end a war that has killed more than 160,000 people.
Brahimi stepped down at the end of May after two rounds of peace talks yielded no concrete results. Syria held controversial elections Tuesday set to re-elect President Bashar al-Assad.