US impeachment inquiry: Subpoena issued to White House

Democrats are trying to build a compelling case for impeachment, not only to convince the American public but also Senate Republicans.

US House Democrats have subpoenaed the White House for documents relating to the impeachment inquiry into the president.

Donald Trump says he would not cooperate until the House of Representatives votes to approve the investigation.

This comes after text messages revealed how much pressure Ukraine’s president was put under to investigate Trump’s political rival, Joe Biden.

Al Jazeera’s Heidi Zhou-Castro reports from Washington, DC.