Leo Varadkar is set to be elected Irish prime minister for the second time on Saturday, taking over from Micheál Martin under a novel rotation agreement struck between their two parties - once sworn rivals - in a 2020 coalition deal.
Martin resigned on Saturday ahead of a vote in parliament to elect Varadkar, who was prime minister from 2017 to 2020. Martin will become deputy prime minister until a scheduled 2025 election and is also expected to be appointed foreign minister.
The 2020 coalition deal - which also included the smaller Green Party - for the first time united Martin's Fianna Fail and Varadkar's Fine Gael, Ireland's dominant centre-right parties and have led every government since independence a century ago.
"This morning, I visited the president and, pursuant to the relevant provisions of Bunreacht na hÉireann (Constitution of Ireland), I have tendered my resignation from the office of Taoiseach (prime minister)," Martin told parliament.
"It is both a privilege and a responsibility to serve as head of government in a free and democratic republic. I have been deeply conscious of this every day I have held the office of Taoiseach."
Varadkar will again face a years-long housing crisis that cost him a full second term in office and has made the left-wing Sinn Fein clear favourite to come out on top at the next election with a consistently wide lead in opinion polls.
Cardinals are scheduled to meet on Tuesday to plan Pope Francis' funeral, which leaders from around the world will attend ahead of a conclave next month to elect a new head of the Roman Catholic Church.
Russian President Vladimir Putin proposed on Monday bilateral talks with Ukraine for the first time since the early days of the war, and his Ukrainian counterpart Volodymyr Zelenskyy said Kyiv was eager to discuss a halt to attacks on civilian targets.
Ukraine issued air raid alerts for Kyiv and the country's eastern half as blasts shook the city of Mykolaiv early on Monday, authorities said, hours after the one-day Easter ceasefire declared by Russian President Vladimir Putin came to an end.
US Vice President JD Vance began a four-day visit to India on Monday and will hold talks with Prime Minister Narendra Modi, as New Delhi rushes to avoid steep US tariffs with an early trade deal and boost ties with the Trump administration.