A second whistleblower with direct knowledge of information regarding the Ukraine scandal has come forward, building more pressure on US president Donald Trump as he faces possible impeachment.

The legal team representing the original whistleblower, whose complaint to the inspector general of the intelligence services lead to the opening of an impeachment inquiry, said they were representing a second whistleblower with “first-hand knowledge” of the accusations contained in the original whistleblower’s account.

Attorney Andrew Bakaj said his firm was now representing “multiple whistleblowers” in connection to the August 12th complaint. “I can confirm that my firm and my team represent multiple whistleblowers in connection to the underlying August 12, 2019, disclosure to the Intelligence Community Inspector General,” he said, adding that there would be no further comment at this time.

According to another attorney, Mark Zaid, the second whistleblower is an intelligence official and has spoken to the inspector general. Unlike the original whistleblower who did not witness the disputed phone call between Mr Trump and Ukrainian president Volodymyr Zelenskiy on July 25th, this individual has “first-hand knowledge” of that event, the lawyer suggested.

US president Donald Trump railed against the ‘do-nothing Democrats’ impeachment on Sunday on Twitter with a string of retweets from supporters. Photograph: Jim Watson/AFP via Getty

‘Keep them coming!’

In one of dozens of tweets and retweets posted by the president over the weekend, Mr Trump hit out at reports of a second whistleblower. “The first so-called second hand information “Whistleblower” got my phone conversation almost completely wrong, so now word is they are going to the bench and another “Whistleblower” is coming in from the Deep State, also with second hand info.”

....And by the way, I would LOVE running against 1% Joe Biden - I just don’t think it’s going to happen. Sleepy Joe won’t get to the starting gate, & based on all of the money he & his family probably “extorted,” Joe should hang it up. I wouldn’t want him dealing with China & U! — Donald J. Trump (@realDonaldTrump) October 6, 2019

NEWS UPDATE: I can confirm this report of a second #whistleblower being represented by our legal team. They also made a protected disclosure under the law and cannot be retaliated against. This WBer has first hand knowledge. https://t.co/zYkUYgJ0mE — Mark S. Zaid (@MarkSZaidEsq) October 6, 2019

He continued: “Meet with Shifty. Keep them coming!” a reference to Adam Schiff, the chair of the House Intelligence Committee which is leading the impeachment inquiry.

The inspector general who has received the two whistleblower complaints testified for six hours before congressional committees on Friday. He originally passed on the first whistleblower’s complaint to the director of national intelligence, but he was advised by the Department of Justice not to transmit that information to Congress.

The prospect of further complaints against the president emerged after the White House was subpoenaed late on Friday for documents related to the Ukraine investigation. The subpoena, which was addressed to acting White House chief of staff Mick Mulvaney, was issued after the White House refused to release documents voluntarily. The House committees also requested information from vice president Mike Pence, secretary of state Mike Pompeo and Mr Trump’s lawyer, Rudy Giuliani.

Biden hits out

However, the White House could refuse to comply, claiming executive privilege, a move that would likely prompt legal action. Mr Pompeo said during a trip to Greece at the weekend that the State Department would follow the law when it comes to subpoenas.

The Democratically-controlled House of Representatives is investigating Mr Trump’s phone call with the Ukrainian president on July 25th, and any attempt by White House officials to conceal evidence that the president was soliciting the help of foreign governments to damage his political rival, Joe Biden.

Mr Biden, who is running to become the Democratic nominee for president, yesterday hit out at the president who claims that the former vice-president’s son profited from his work in Ukraine and China due to his father’s position. In an opinion piece in the Washington Post, Mr Biden accused Mr Trump of abusing the office of president.

“Enough is enough. Every day – every few hours, seemingly - more evidence is uncovered revealing that President Trump is abusing the power of the presidency and is wholly unfit to be president,” Mr Biden wrote. “He is using the highest office in the land to advance his personal political interests instead of the national interest.”

He added: “He does not understand the immense responsibility demanded of all those who hold the office of the president of the United States. ”