Former Thai premier Yingluck Shinawatra said on Friday she would fight a government order demanding she personally pay nearly $1 billion in compensation for a rice policy prosecutors say was riddled with graft.

Yingluck, Thailand's first female premier, was removed from office by a court days before the army seized power in a 2014 coup.

She has since been tangled in a web of legal cases that she said are politically motivated, including a criminal negligence trial over the rice policy that could see her jailed for up to 10 years.

Outside the court on Friday, she told reporters she received an order signed two days ago demanding more than $1 billion in civil damages for the rice scheme.

"Such an order has violated my rights and is not fair," she said as supporters greeted her outside the Bangkok courthouse.

"I affirm that I will exercise all my rights to deny this allegation and the civil charges," she said.

She added that she would not comment further as the country is still grieving the death last week of its revered monarch Bhumibol Adulyadej.

But she has previously called on the government to file civil claims in court instead of ordering the $1 billion fine - a figure that dwarfs the $17.4 million she declared in assets in 2015.

She can now petition an administrative court to block or withdraw the order.

In addition to cases against Yingluck and senior members of her former cabinet, the government is investigating some 850 cases related to the rice scheme for graft, government spokesman General Sansern Kaewkamnerd said.

Under the rice scheme, Yingluck's government purchased paddies from farmers at nearly twice the market rate.

The policy was wildly popular among farmers in the northeast - a key support base for her political party - but pilloried by critics as a costly and corrupt populist handout.

Yingluck insists the rice scheme was a measure to help the poor in Thailand's rural heartlands, a demographic for years ignored by Bangkok's military-allied elite.

Parties backing Yingluck and her billionaire brother Thaksin Shinawatra, a former premier ousted in a 2006 coup, have won every election in the past decade with support from the populous but poor north.

Thaksin has been living abroad in self-imposed exile for years to avoid serving a prison sentence after being convicted of corruption.