U.S. Secretary of State John Kerry's latest proposal for closer U.S.-Russian cooperation against extremist groups in Syria is drawing questions over Russia's intentions from skeptics in the U.S. government, European nations in the coalition against the Islamic State and the main Syrian opposition groups.
Several U.S. military and intelligence officials called the plan naive and said Kerry risks falling into a trap that Russian President Vladimir Putin has laid to discredit the United States with moderate rebel groups and drive some of their fighters into the arms of the Islamic State and other extremist groups.
Some European members of the coalition against Islamic State forces have expressed concern about sharing intelligence with Russia, which they say has been an untrustworthy partner in Syria.