Japanese Prime Minister Shinzo Abe, the nation’s longest serving premier, is set to resign due to his worsening health.

Japan’s Prime Minister Shinzo Abe wearing a protective face mask arrives at his official residence, amid the coronavirus disease (COVID-19) outbreak, in Tokyo, Japan August 28, 2020.

“The resignation is a done deal,” said the source close to a senior official in Abe’s Liberal Democratic Party. Abe has battled the disease ulcerative colitis for years and two recent hospital visits within a week fanned questions on whether he could stay in the job until the end of his term as ruling party leader, and hence, premier, in September 2021. Abe was scheduled to hold a news conference at 5:00 p.m. (0800 GMT). As the news spread, Japan’s benchmark Nikkei average .N225 fell 2.12% to 22,717.02, while the broader Topix .TOPX shed 1.00% to 1,599.70.

Abe’s resignation will trigger a leadership race in the LDP, the winner of which must be formally elected in parliament. The conservative Abe returned as prime minister for a rare second term in December 2012, pledging to revive growth with his “Abenomics” mix of hyper-easy monetary policy, fiscal spending and reforms. He also pledged to beef up Japan’s defences and aimed to revise the pacifist constitution. On Monday, Abe surpassed a record for longest consecutive tenure as premier set by his great-uncle Eisaku Sato half a century ago. Under fire for his handling of the novel coronavirus pandemic and scandals among party members, Abe has recently seen his support fall to one of the lowest levels of his nearly eight years in office.