This was announced by the White House spokesperson Josh Earnest at a briefing, Censor.NET reports citing The Washington Times.
The White House spokesman said the Russian offer to send a high-level team headed by Prime Minister Dmitry Medvedev to Washington was a sign of desperation for Mr. Putin's air campaign in support of Mr. Assad, but Mr. Putin said the rejection represented the deeply muddled thinking in the U.S. and other parts of the West about the need to act decisively against Islamic State militants fighting the Syrian leader.
"How is it possible to work together?" Mr. Putin asked at an investment forum in Moscow. "I think some of our partners simply have mush for brains. They do not have a clear understanding of what really happens in [Syria] and what goals they are seeking to achieve."
According to Earnest, the U.S. continues to watch Iran building up its presence in Syria. He stressed this is a sign of Russia's isolation from the rest of the world, for the only parties according with them at the moment are Assad's regime and the Iranians, who have been involved in destabilizing activities inside Syria.
Russian Foreign Minister Sergey Lavrov said Moscow offered to send Mr. Medvedev and a delegation to the U.S. "to agree on a number of joint steps" over Syria.
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