US Secretary of State Mike Pompeo has been ordered by Democrats to turn over documents relating to the Trump administration’s dealings with Ukraine.
In a letter, the heads of three House committees subpoenaed Pompeo to produce the documents within a week.
It is the latest move in rapidly escalating impeachment proceedings against President Donald Trump.
Press here to see letter with which three House committees subpoenaed Pompeo
He is being scrutinised for allegedly pressuring Ukraine’s president to investigate Democratic rival Joe Biden.
In a separate development on Friday, the US special envoy for Ukraine negotiations, Kurt Volker, resigned, US media reported.
r Trump has denied putting any pressure on Ukrainian President Volodymyr Zelensky in a phone call in July, when Biden was leading polls to win the Democratic nomination for the White House race in 2020.
Trump has alleged that Biden pressed for the sacking of Ukrainian prosecutor Viktor Shokin in 2016 to protect a business that employed his son, Hunter Biden.