BANGKOK — Thai Prime Minister Yingluck Shinawatra said Monday she will dissolve the lower house of Parliament and call elections in an attempt to calm the country’s deepening political crisis.
Yingluck’s announcement came as thousands of antigovernment protesters began marching through Bangkok in a ‘‘final showdown’’ against her government.
‘‘After listening to opinions from all sides, I have decided to request a royal decree to dissolve Parliament,’’ Yingluck said in a televised statement. ‘‘There will be new elections according to the democratic system.’’
She did not immediately set a date and it was unclear whether the move would ease the country’s political standoff, which deepened Sunday after the main opposition Democrat Party resigned from the legislature en masse.
Democrat Party spokesman Chavanond Intarakomalyasut said his party could not participate in the Legislature anymore because the body is ‘‘no longer accepted by the people.’’
Protest leader Suthep Thaugsuban called on supporters to stay peaceful, but many fear the day could end violently when demonstrators converge from nine locations on Yingluck’s office at Government House. More than 60 Thai and international schools in Bangkok have closed as a precaution.
Thailand has been plagued by political turmoil since the army toppled Prime Minister Yingluck Shinawatra’s brother Thaksin in a 2006 coup. In broad terms, the conflict pits the Thai elite and the educated middle-class against Thaksin’s power base in the countryside, which benefited from populist policies designed to win over the rural poor.
‘‘We will rise up. We will walk on every street in the country. We will not be going home again,’’ said Suthep, whose supporters have occupied the Finance Ministry and part of a vast government complex for more than a week. ‘‘The people who will be going home empty-handed are those in the Thaksin regime.’’
Since the latest unrest began last month, at least five people have been killed and 289 injured. Violence ended suddenly last week as both sides paused to celebrate the birthday of the nation’s revered king, Bhumibol Adulyadej, who turned 86 Thursday.
Late Sunday, a group of hooded and masked men crept in the dark toward a police post at Government House and attacked it with slingshots loaded with nails and sharp metal projectiles, according to Police Major General Piya Uthayo. Police did not respond, and the assailants retreated, he said. There were no injuries.
Democrat leader and former premier Abhisit Vejjajiva said Yingluck’s government has been ‘‘illegitimate’’ ever since her ruling Pheu Thai party tried to ram through an amnesty bill that critics allege was mainly designed to bring back Thaksin from exile, Abhisit said. Thaksin lives in Dubai to avoid a jail sentence for a corruption conviction he says was politically motivated.
‘‘The solution to our current problems needs to start with the showing of responsibility,’’ Abhisit said. ‘‘The prime minister has never showed any responsibility or conscience.’’
He also criticized Yingluck’s party for trying to amend a clause in the constitution that would have transformed the Senate into a fully elected body.