Tony Blair's spokesman has refused to be drawn on claims that the former British prime minister is seeking to become US President Donald Trump's Middle East envoy.

Blair met the president's son-in-law and key adviser Jared Kushner at the White House last week to discuss working for Trump, according to the Mail on Sunday.

A spokesman for the former PM told the Press Association: "I'm not going to comment on private conversations."

The newspaper said Blair has met Kushner three times since September.

After leaving Downing Street, Blair took the role of Middle East envoy for the Quartet Group comprising the EU, US, Russia and UN.