President Donald Trump has made his possible legal problems worse by saying he did not have tapes of his conversations with former FBI director James Comey, according to Norm Eisen, who served as ethics attorney during President Barack Obama's tenure.

Trump said Thursday he did not make and does not have any recordings of their talks.

"This lie increases Trump's legal exposure for obstruction and witness intimidation — more evidence of corrupt intent," Norm Eisen wrote on Twitter.

This lie increases Trump's legal exposure for obstruction and witness intimidation--more evidence of corrupt intent @Susan_Hennessey https://t.co/qBx7e58XEl — Norm Eisen (@NormEisen) June 22, 2017

After firing Comey in May, Trump said in a May 12 tweet Comey "better hope" no tapes existed of their talks.

James Comey better hope that there are no "tapes" of our conversations before he starts leaking to the press! — Donald J. Trump (@realDonaldTrump) May 12, 2017

Eisen is suing Trump for violating the emoluments clause of the Constitution, and said Trump is "becoming more and more brazen in his efforts to monetize the presidency."