Sunday on 'This Week':​ House Speaker Nancy Pelosi, Amb. Robert O'Brien

ABC News Chief Anchor George Stephanopoulos goes one-on-one exclusively with Speaker of the House Nancy Pelosi to discuss the latest on impeachment and Iran, only on “This Week” Sunday.

Plus, White House National Security Adviser Robert O'Brien joins “This Week” to discuss the Trump administration’s response on Iran.

And the Powerhouse Roundtable debates all the week’s politics, with former New Jersey Governor and ABC News Contributor Chris Christie, Washington Post Congressional Reporter Rachael Bade, TIME National Political Correspondent Molly Ball, and Open Society Foundations President Patrick Gaspard.

Like “This Week” on Facebook here. You can also follow the show on Twitter here.