CIA director and secretary of state nominee Mike Pompeo said Thursday that he had been interviewed by Special Counsel Robert Mueller, who is investigating links between the Trump campaign and Russia in the 2016 election.

Pompeo, who reportedly had been asked by President Donald Trump to intervene in the Russia probe, confirmed the Mueller interview during a hearing into his nomination to become US secretary of state.

“I spoke with Special Counsel Mueller who interviewed me, requested an interview,” he said. “I cooperated.”

But he refused to give details.

Last year, The Washington Post reported that in a March 2017 White House meeting, Trump asked Pompeo and Director of National Intelligence Dan Coats to try to get the FBI to back off of an investigation into Trump’s former national security advisor Mike Flynn.

Flynn has since been indicted by Mueller for lying about his contacts with Russians.

Coats later reported that conversation with other officials, and decided that it would be improper to intervene with the FBI, according to the Post.

According to separate reports, Pompeo was later among several senior administration officials asked by Trump to contact media on his behalf to defend his image.

Pompeo, who after 15 months at the Central intelligence Agency was nominated by Trump to replace secretary of state Rex Tillerson, declined to give details of his conversations with Mueller investigators, or confirm any discussions with Trump on the Russia probe.

“I have cooperated with multiple investigations,” he told the Senate Foreign Relations Committee.

“I think it’s most important that while these investigations continue, I not speak to the conversations I have had with the various investigative bodies.”