Updated

Thailand's prime minister announced Monday she will dissolve the lower house of Parliament and call elections in an attempt to calm the country's deepening political crisis. The surprise move came as 100,000 protesters vowing to overthrow her government marched through the streets of Bangkok for a "final showdown."

Prime Minister Yingluck Shinawatra's appeared emotional and her voice shook as she spoke in a nationally televised address Monday morning.

"After listening to opinions from all sides, I have decided to request a royal decree to dissolve Parliament," Yingluck said, breaking into regular programing. "There will be new elections according to the democratic system."

She said the Election Commission would set a date "as soon as possible."

It was unclear whether the move would ease the country's political standoff, which deepened Sunday after the main opposition party resigned from the legislature en masse.  Protest leader Suthep Thaugsuban has repeatedly said that calling fresh elections would not be enough to end the conflict, and he made no immediate comment on Yingluck's announcement.

Police estimated that about 100,000 protesters were out on the streets of the Thai capital.

Thailand has been plagued by political turmoil since the army toppled Yingluck'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," Suthep said Sunday. His 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."

Many feared 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.

As Yingluck spoke, long columns of protesters paralyzed traffic on major Bangkok boulevards. They filled a major four-lane road in the city's central business district, waving flags, blowing whistles and holding a huge banner that said, "Get Out Shinawatra."

Since the latest unrest began last month, at least five people have been killed and at least 289 injured. Violence ended suddenly last week as both sides paused to celebrate the birthday of the nation's revered king, who turned 86 Thursday.

The crisis boiled over after Yingluck's ruling party tried to ram a controversial amnesty bill through the legislature. Critics say it was designed mainly to bring back Thaksin, who lives in self-imposed exile in Dubai to avoid jail time for a corruption conviction he says was politically motivated.

Abhisit Vejjajiva, the leader of the Democrat party and a former premier, said Yingluck's government had become "illegitimate" since then, and his party had no choice but to pull out of the lower house. The Democrats held 153 of the 500 seats in the legislative body, according to the latest figures on their website. Abhisit said the resignations were effective immediately.

"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."

The minority Democrats -- who are closely allied with the protesters -- have not won an election since 1992, and some of their leaders appear to have given up on electoral politics as a result. The protesters are demanding a non-elected "people's council" lead the country instead.

Yingluck's government, by contrast, came to power in a landslide vote in 2011 that observers said was free and fair.

In a speech Sunday, Yingluck said again that she was not trying to cling to power and would be "happy to resign" and dissolve Parliament if that could ease the crisis. But she said those things could only happen if new elections are organized within 60 days and all parties accept the outcome.

Suthep has repeatedly rejected those initiatives and refused to negotiate.

Yingluck also reiterated an offer to set up a national forum to find a way out of the crisis. She said if there was still no resolution, a national referendum could be held, but she did not specify on what.

Any "government that comes to power without elections would significantly affect our image and confidence in the country," Yingluck said, referring to Suthep's demand for a specially appointed people's council to rule.