The Biden administration has made a “substantial offer” to bring back two American citizens detained in Russia, BBC reported on Thursday.
According to reports Moscow has shown interest in exchanging American basketball star Brittney Griner for convicted Russian arms trafficker Viktor Bout.
Secretary Antony Blinken said he would raise the matter in a call next week with Russia’s foreign minister.
Blinken and Sergei Lavrov have not spoken since the war in Ukraine began.
However, both the White House and the Department of State declined on Wednesday to disclose details of the proposed deal, in which the US hopes to trade Bout for Ms Griner and fellow American detainee Paul Whelan.
The New York Times reports that the US last month offered Russia to swap Bout for Ms Griner and Whelan, and that President Joe Biden had approved the offer.
Bout, dubbed the merchant of death, is currently serving a 25-year prison sentence in the US on charges of attempting to sell weapons to a Colombian rebel group to kill Americans.
White House spokesman John Kirby confirmed an offer had been made “several weeks ago”, but noted Russia “hasn’t favourably engaged so far”.