A lawyer for former US national security adviser Michael Flynn has told President Donald Trump’s legal team that they are no longer communicating with them about special counsel Robert Mueller’s investigation into Russian election interference.

The decision could be a sign that Flynn is moving to co-operate with Mueller’s investigation or negotiate a deal for himself.

The decision was communicated this week, said a person familiar with the decision who spoke to The Associated Press on condition of anonymity to discuss an ongoing investigation.

In large criminal investigations, defence lawyers routinely share information with each other. But it can become unethical to continue such communication if one of the potential targets is looking to negotiate a deal with prosecutors.

A lawyer for Flynn didn’t respond to a request for comment. A lawyer for Flynn’s son, Michael Flynn Jr, who has also come under investigation from Mueller’s team of prosecutors, declined to comment.

Flynn was forced to resign as national security adviser in February after White House officials concluded he had misled them about the nature of his contacts during the transition period with the Russian ambassador to the US.

He was interviewed by the FBI in January about his communications with the ambassador Sergey Kislyak.

The deputy attorney general at the time, Sally Yates, soon advised White House officials their public assertions that Flynn had not discussed sanctions with Kislyak were incorrect and that Flynn was therefore in a compromised position.

– AAP