President Donald Trump has said he likes “the idea” of testifying in the impeachment inquiry against him.
In a tweet on Monday Mr Trump said he would “strongly consider” the move after House Speaker Nancy Pelosi suggested it over the weekend.
The Democrat-led inquiry is establishing whether Mr Trump withheld aid to Ukraine in return for an inquiry into ex-Vice President Joe Biden.
The Republican president has dismissed it as a “witch hunt”.
On Sunday, Ms Pelosi said the president was welcome to “speak all the truth that he wants if he wants” before investigators.
“If he has information that is exculpatory, that means ex, taking away, culpable, blame, then we look forward to seeing it,” she told the CBS News programme Face the Nation.
In his tweets, Mr Trump attacked Ms Pelosi as “Our Crazy, Do Nothing” speaker, but said he would consider testifying “in order to get Congress focused again”.
The president has recently faced renewed criticism for his use of Twitter. Chuck Schumer, the Democratic leader in the Senate, told reporters that if Mr Trump “doesn’t like what he’s hearing, he shouldn’t tweet”, but instead “testify under oath”.
His comments came after Mr Trump tweeted attacks on a witness – Marie Yovanovitch, the former US ambassador to Ukraine – while she was testifying to Congress on Friday.
Ms Yovanovitch said it was “very intimidating”, which Mr Trump denied.
Ms Yovanovitch was removed as ambassador to Kyiv in May, two months before a controversial phone call between Mr Trump and his Ukrainian counterpart, Volodymyr Zelensky, which is now key to the inquiry.
A rough transcript of the call revealed that Mr Trump had urged President Zelensky to investigate unsubstantiated allegations against Mr Biden and his son Hunter, who sat on the board of a Ukrainian gas company.
In the latest development, state department official David Holmes told investigators in closed door testimony on Saturday that he had overheard a US diplomat telling Mr Trump that Ukraine would carry out investigations the president had asked for.