A top member of Donald Trump's administration has business links with Russian allies of President Vladimir Putin who are under US sanctions, the Paradise Papers have revealed.

Commerce Secretary Wilbur Ross has an interest in Navigator Holdings, which earns millions a year transporting oil and gas for Russian energy firm Sibur.

Two major Sibur shareholders are under some form of US sanctions.

A commerce department spokesman did not dispute the revelations.

"Secretary Ross recuses himself from any matters focused on transoceanic shipping vessels," the spokesman told BBC Panorama, adding that the secretary "works closely with Commerce Department ethics officials to ensure the highest ethical standards".