Trump news: US nuclear arsenal now 'in tippy-top shape' says president when asked about responding to Iran: 'We should all pray we don't have to use them'

Andrew Buncombe, Joe Sommerlad, Lily Puckett
Donald Trump: Nicholas Kamm/AFP/Getty

Donald Trump has defended himself on Twitter as his administration faces an extraordinary showdown with Congress after acting national intelligence director Joseph Maguire withheld a whistleblower’s complaint understood to concern a private conversation between the president and a foreign leader, despite its being classified a matter of “urgent concern”.

He also told reporters that they should "look into Joe Biden" when asked about the whistleblower's complaint, in an angry press conference in the Oval Office, during which he called the whistleblower "bipartisan," though he said he did not know who the person was.

Later, The Wall Street Journal reported that the president asked Volodymyr Zelensky, the Ukranian president, to investigate Joe Biden's son "about eight times" during one phone call in July.

The White House said the president will meet with Mr Zelensky next week.

The House Intelligence Committee has not ruled out going to court to force Mr Maguire’s hand, according to the panel’s chairman Adam Schiff, as The Washington Post and New York Times report at least part of the mystery complaint involves Ukraine.

The president’s former secretary of state Rex Tillerson has meanwhile told Harvard University that the administration “got played” by Israeli prime minister Benjamin Netanyahu, whom he described as “a bit Machiavellian”.

The president did not mention Friday's wildly successful climate strike at all today.

Please allow a moment for our liveblog to load