Rudy Giuliani said Friday that he won’t testify before the House of Representatives as part of its impeachment inquiry unless he gets the go-ahead from President Donald Trump.

“Ultimately, if I were to say yes and he were to say no, I can’t testify,” Giuliani, who is Trump’s personal attorney, told CNN.

Giuliani has functioned as an emissary from Trump — and, he claims, the State Department — to press Ukraine to launch an investigation into Trump’s political rival Joe Biden and Biden’s son Hunter Biden. Giuliani has claimed without evidence that when Biden was vice president he attempted to block an investigation into a Ukrainian energy company whose board of directors included Hunter Biden.

Trump is the now the target of an impeachment inquiry for his phone call in July with Ukrainian President Volodymyr Zelensky, in which Trump pressed the foreign leader to launch a Biden investigation while holding up military funds to the nation.

Giuliani has also claimed — again without evidence — that information that led to criminal charges against Trump’s former campaign manager Paul Manafort were part of a Democratic plot to interfere with the 2016 election. Manafort is serving seven years in prison on a variety of charges, including federal fraud and conspiracy offenses.

Giuliani told CNN that his work for the president would be protected by attorney-client privilege — even though he has already discussed much of his work on behalf of Trump in Ukraine on national TV.

Giuliani said he hasn’t discussed with Trump the possibility of testifying, nor has anyone in the House contracted him about doing so.

House Intelligence Committee member Rep. Mike Quigley (D-Ill.) told CNN on Friday that he has several questions for Giuliani, including if he has a security clearance.

“Rudy may be the best source of information because he doesn’t know what he shouldn’t say,” said Quigley.