Former US national security adviser John Bolton: Has crucial knowledge of the president’s actions and conversations regarding Ukraine that could fill out key blanks in the narrative of the impeachment case. Photograph: Sergei Gapon/AFP via Getty Images

Former US national security adviser John Bolton has said he will testify in the Senate impeachment trial of President Donald Trump if subpoenaed, incr(...)

Former White House national security aide Fiona Hill testifying before the House intelligence committee on Capitol Hill in Washington on Thursday. Photograph: Erin Scott/Reuters

Donald Trump’s troubles have deepened after the impeachment inquiry against the US president this week heard some of the most damning evidence yet tha(...)

US president Donald Trump at the Economic Club in New York. Photograph: Demetrius Freeman/Bloomberg

Turkish president Recep Tayyip Erdogan will meet US president Donald Trump in the White House on Wednesday, in the first face-to-face meeting between (...)

Chairman of the House Intelligence Committee Adam Schiff will control most of the questioning.   Photograph: Reuters/Joshua Roberts/File Photo

Millions of Americans are expected to tune into TV screens on Wednesday as the first public hearings in the impeachment inquiry into US president Dona(...)

Representatives Mark Meadows, Jim Jordan and  Michael Conway  speak to reporters outside a closed-door deposition  as part of the US House of Representatives impeachment inquiry. Photograph: Erin Scott/Reuters

Democrats in Congress, answering Republican complaints that their impeachment investigation of US president Donald Trump is being conducted in secret,(...)

More than two dozen Republican politicians speak to the media after storming into the room used by the House of Representatives’ impeachment inquiry into US president Donald Trump. Photograph: Jim Lo Scalzo/EPA

A US House of Representatives impeachment inquiry devolved into chaos on Wednesday as Republican politicians, encouraged by US president Donald Trump (...)