By Evelyn Leopold UNITED NATIONS, Jan 9 (Reuters) - Russia wants the U.N. Security Council to find out which nations are not cooperating fully with an investigation into political murders in Lebanon, Moscow's ambassador said on Tuesday. But France, among other Western council members, disagree with putting such a request to Serge Brammertz, head of a U.N. probe into the 2005 assassination of former Lebanese Prime Minister Rafik al-Hariri and 15 other politically motivated attacks. Russia is an ally of Syria, which many Lebanese blame for the killings. Last month, Brammertz told reporters he had sent out more than 60 requests "to an important number of countries and today there are more than 20 still not answered." This, he said impeded the work of his commission. Brammertz did not name the countries. Russia's U.N. Ambassador Vitaly Churkin wants to know who they are, saying the council should ask the prosecutor "to be more specific next time he reports to the council in March." "He gave this rather strong signal, so the signal has to be taken up," Churkin told reporters. "We should face our own political responsibilities as the Security Council," which authorized the investigation. Churkin noted that reports by Brammertz said Damascus had been cooperating. "Let us face it. If we focus so hard on one country why should we disregard completely or even not want to know what those countries are," Churkin said. Syria denies involvement in the Hariri slaying, which took place after the former prime minister accused Damascus of meddling in Lebanese politics. Street protests in Lebanon after the killing prompted Syria to withdraw forces that had been in the country for 22 years. Behind closed doors in council consultations, participants said supporters of Russia, such as Qatar, South Africa and Indonesia, made the point that the council should be even-handed and not just point at one country -- a reference to Syria, the subject of several council resolutions. Other diplomats said that Brammertz, in private contacts, said he preferred to pursue his search for intelligence or financial records on a bilateral basis rather than a name-and-shame session of nations in the council. Syria's U.N. Ambassador Bashar Ja'afari singled out France, instrumental with the United States in getting the council to approve the Hariri probe, as blocking the letter to Brammertz. "The Russian initiative is against singling out a country for political purposes," he said. "It goes toward knowing precisely those countries that have cooperated and those that have not." The Security Council will return to the issue later in the week, said Churkin, this month's council president.