Thailand's top court on Wednesday sentenced ousted premier Yingluck Shinawata to five years in prison for criminal negligence

Bangkok: Thailand's top court on Wednesday sentenced ousted premier Yingluck Shinawata to five years in prison for criminal negligence, a verdict read in absentia after she fled the kingdom last month.

Shinawata's administration was toppled in a 2014 coup and she was later put on trial for negligence over her government's rice subsidy scheme, which is said to have cost billions of dollars.

She pleaded innocent and accused the ruling junta of a political witch-hunt.

But the Supreme Court in Bangkok deemed her guilty on Wednesday, saying she failed to stop corruption and losses in the rice programme.

"The court found that the defendant is guilty as charged...the court has sentenced her to five years in prison and the court also unanimously agreed that the sentence will not be suspended," a judge said.

The verdict, which makes Shinawata's return to the kingdom increasingly unlikely, said the leader "should have designated reasonable and effective regulations that could concretely prevent loss from the beginning of the programme."

"The defendant did not take such precaution therefore contributing to huge losses to farmers, state budget, ministry of finance, the country and the people," it said.

After attending dozens of hearings in a trial that lasted more than one year, Shinawata failed to turn up for a ruling originally scheduled for 25 August, a day of high drama that left the kingdom dumbfounded.

The 50-year-old has not made any public appearance or comments since pulling the vanishing act. But there are widespread reports she joined her billionaire brother Thaksin, a former prime minister ousted in a 2006 coup, in Dubai.

Thaksin has kept a home in the city since he fled Thailand in 2008 to avoid jail for a corruption conviction.

The two siblings lie at the heart of a political battle that has gnawed at Thailand for more than a decade.

Emerging on the scene in 2001, they won the loyalty of the rural and urban poor with groundbreaking welfare schemes in a sharply unequal country.

But their rise angered Bangkok's army-allied elite, which repeatedly assailed their elected governments with coups or court rulings.

Shinawata's downfall revolved around a scheme that saw her government purchase rice from farmers at nearly twice the market price.

It was wildly popular in the rural heartlands but slammed by critics as a costly and graft-riddled handout.

"There was corruption in every step if the rice pledging programme," the court verdict said, adding that it cost the country nearly $10 billion.

Where is Yingluck Shinawata?

Thailand's junta leaders deny having any prior knowledge of Shinawata's plan to escape.

But many are unconvinced, given the junta's tight security net and round-the-clock surveillance of the former leader over the course of the trial.

Analysts say Shinawata likely cut a deal with the military leaders, who are bent on erasing her powerful clan from the political scene.

"By getting Shinawata out of Thailand, the military gets rid of a potential thorn in their side who could become a martyr if jailed, or a powerful politician again if she is not," said Paul Chambers, an expert on Thai politics.

On the eve of the verdict junta chief Prayut Chan-O-Cha declared his "spies" had informed him of Shinawata's whereabouts, but said he would not reveal her location until after the judgment was delivered.

With both Shinawata and Thaksin now in exile, there are major questions about the future of their political dynasty and the pro-democracy "Red Shirt" movement formed by their supporters.