Following Parliament’s rejection of Prime Minister Boris Johnson’s Brexit proposal this week, the EU has once again deferred Britain’s deadline to leave, granting a 90-day extension until January 31.At the center of the Brexit turmoil is the island of Ireland. The sovereign Republic of Ireland is of course a member of the EU, and Northern Ireland remains part of the United Kingdom. Twenty-one years after the signing of the Good Friday Agreement, which brought a fragile peace to the Republic of Ireland and Northern Ireland, new conflict over a possible customs border has energized calls for a united Ireland. Across the Irish Sea, there is also growing support for a second referendum on Scottish independence. NPR’s London Correspondent Frank Langfitt joins Tom Hall from Belfast with the latest.