The Biden administration has made a “substantial offer” to bring two American detainees home from Russia.
Reports have suggested Moscow is interested in trading basketball star Brittney Griner for convicted Russian arms trafficker Viktor Bout.
US Secretary Antony Blinken said he would raise the matter in a call next week with Russia’s foreign minister.
Mr Blinken and Sergei Lavrov have not spoken since the war in Ukraine began.
Speaking to reporters at the State Department, Mr Blinken said he could not reveal details of the proposed swap.
According to CNN, the US hopes to trade Bout for Griner and fellow American detainee Paul Whelan.