Moscow, Russia - US Central Intelligence Agency Director John Ratcliffe visited Moscow on Tuesday for meetings, in what would be his first known visit to Russia as CIA head.

The purpose of the reported visit was not immediately clear, and there was no immediate comment from the CIA or the White House when contacted by AFP.

CBS News quoted sources familiar with the matter as confirming Ratcliffe's trip, while Axios separately reported on the visit, quoting two US officials.

Data from tracking site Flightradar24 had earlier shown a US military C-17 travelling from the United States to Latvia and then on to Moscow's Vnukovo airport.

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The data showed the same plane leaving Moscow several hours later.

When asked earlier Tuesday about the arrival of a US military plane in Moscow, the Kremlin's spokesman Dmitry Peskov said he did "not have such information."

The alleged visit comes amid escalating tensions in the Ukraine war, and as US-brokered talks aimed at ending the four-and-a-half-year conflict remain at a standstill.

Civilian casualties in Ukraine soared to their highest since 2022 last month, according to UN data, while Kyiv has ramped up retaliatory strikes deep inside Russia.

The US and Russia have also reached an impasse on nuclear arms control – their last nuclear arms limitation treaty, New START, expired in February.