Moscow: The US declined to host a high-ranking Russian delegation on Syria and also refused to send its own mission to Moscow, Russia’s foreign minister said on Wednesday.

On Tuesday, Russian President Vladimir Putin accused Washington of refusing to cooperate and share intelligence on Syria and said he was willing to send a high-profile delegation led by Prime Minister Dmitry Medvedev to the United States.

“Literally today, we got a reply,” Russian Foreign Minister Sergei Lavrov said, speaking in parliament.

“We have been told that they can’t send a delegation to Moscow and they can’t host a delegation in Washington either,” he said.

Putin, speaking at an investment forum on Tuesday, said Russia’s delegation could include military officials at the level of deputy chief of the General Staff as well as members of security services.

“It is time to take this work to a serious, substantial level, if we really want to work effectively,” Putin said.

But Putin also expressed some of his strongest criticism yet of Washington’s handling of the Syrian crisis, saying the United States did not seem to know what its goals were in the Middle Eastern country.

“I believe some of our partners simply have mush for brains,” he said.

Late last month Moscow launched a bombing campaign in Syria, saying it needed to target Daesh terrorists before they cross into Russia, which has a large Muslim population.

But Washington and its allies slammed Russia’s intervention in the multi-front conflict, saying Moscow was also targeting Western-backed moderate rebels and seeking to prop up the regime of Bashar Al Assad.