Kremlin aide Yuri Ushakov said on Wednesday that the latest US peace plan for Ukraine required “serious analysis” by Moscow and had not been discussed between US and Russian officials at a meeting in Abu Dhabi this week.

Ushakov said representatives of Russia’s intelligence services had been in the Gulf city to meet their Ukrainian counterparts and discuss “very sensitive issues,” including prisoner exchanges.

While there, they also met US Army Secretary Dan Driscoll, a US official told Reuters on Tuesday.

Ushakov said the meeting with the US official had been unexpected, and that the latest US-drafted peace plan had not been not discussed. He did not say what they had actually talked about.

“No, the peace plan was not discussed in Abu Dhabi. The peace plan has not yet been discussed in detail with anyone,” Ushakov told Russian state TV reporter Pavel Zarubin.

“We saw it, it was passed on to us, but there haven’t been any discussions yet.”

Ushakov added that the proposals required “truly serious analysis, serious discussion.”

“Some aspects can be viewed positively, but many require specialized discussion among experts,” he said.