A second whistleblower has come forward as part of an impeachment investigation into Donald Trump.
The anonymous source reportedly has first-hand knowledge of the US president’s dealings with Ukraine and has spoken to the country’s inspector general.
Lawyer Mark Zaid confirmed in an interview with ABC that the second whistleblower also works for US intelligence.
Mr Zaid represents the first whistleblower who filed a complaint involving a July 25 phone call Mr Trump held with Ukraine's president Volodymyr Zelensky.
The US leader is accused of coercing Mr Zelensky into “digging up dirt” on his Democratic rival, former Vice President Joe Biden.
In light of the whistleblower’s complaint, the Democrats launched formal impeachment proceedings against the president.
He has repeatedly denied any wrongdoing and called the investigation a “witch hunt”.
No details have yet been released about the second whistleblower's claims.
However, on Friday, the New York Times reported that a second person was considering coming forward with "more direct information" about the events surrounding the now infamous call.
It is not yet known if this is the person represented by Mr Zaid.
Mr Trump's personal lawyer Rudy Giuliani said he was not surprised there was another "secret source".
Denouncing the revelations on Twitter, he took the opportunity to again accuse Joe Biden's son Hunter of corrupt dealings in Ukraine.
The White House insists it has been open and released a transcript of the call, after the concerns came to light.
However, investigators point out that the published version was redacted and therefore key elements could have been omitted.
Mr Trump has not yet commented directly on news of the second whistleblower.
Instead, he took to Twitter on Sunday to disparage the "Do Nothing Democrats", before adding: "95% Approval Rating in Republican Party. Thank you!"
