A Democrat Party spokesman said his party could not participate in the legislature anymore because the body is "no longer accepted by the people."

Thailand’s main opposition party resigned from Parliament on Sunday to protest what it called “the illegitimacy” of an elected government with which it can no longer work. The move deepens the country’s latest political crisis one day before new street demonstrations that many fear could turn violent.

A Democrat Party spokesman said his party could not participate in the legislature anymore because the body is “no longer accepted by the people.”

The minority Democrats are closely aligned with anti-government protesters who have staged the country’s biggest rallies in years. The demonstrations began last month and are aimed at ousting Prime Minister Yingluck Shinawatra.

At least five people have been killed and at least 289 injured since the latest unrest began.

In a speech on Sunday, Ms. 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 organised within 60 days and all parties accept the outcome.

Protest leader Suthep Thaugsuban has repeatedly rejected those initiatives.

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

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