Lesotho's Prime Minister Thomas Thabane has denied reports that he has fled to South Africa after he failed to appear in court to face charges of murdering his estranged wife in 2017.

He has gone there for a medical check up instead, his office said.

His current wife Maesaiah Thabane has already been charged with the murder.

Mr Thabane would be the first African leader to be charged with a domestic murder while in office, in a case that has shocked the tiny mountain kingdom.

His office says he respects the rule of law and that he plans to appear before the court when he returns from South Africa.

In January, Mrs Thebane went to South Africa, which entirely surrounds the landlocked nation, after police issued a warrant of arrest against her.

Police on Thursday said the prime minister would be charged with murder on Friday. He was expected in court at 09:00 local time (07:00 GMT), reports the Reuters news agency.

Deputy Commissioner of Police Paseka Mokete told reporters he was not aware of Mr Thabane's whereabouts, but said that if he was out of the country receiving treatment then they would wait to resume the case when he returns.

"We cannot at this stage say he is contemptuous [of the court]," he added.

Mr Thabane's previous wife Lipolelo Thabane, 58, was shot dead in the capital, Maseru, two days before Mr Thabane became prime minister in 2017.

He said on state radio on Thursday that he had served the nation "diligently" and he would retire at the end of July.

"I've worked for a peaceful and stable Lesotho. Today... at my age, I have lost most of my energy," he was quoted as saying.

He did not mention the allegations against him.

The ruling All Basotho Convention had given him a deadline of Thursday to resign.

Pressure on PM Thabane has not relented back at home, despite him being in South Africa to receive medical treatment.

There is heavy police presence in the Maseru Magistrates Court - with a handful of his supporters waiting to see how the day will unfold.

The police boss Holomo Molibeli told the BBC that with Mr Thabane's health allowing, they still intend to have the him brought to court on Friday.

His party the All Basotho Convention (ABC), the largest member in a coalition government, is scrambling behind the scenes to agree on his successor. Many within his government want him out - so that he faces the criminal charges as an ordinary citizen.

This is unchartered territory for Lesotho. If he is formally charged while still in office it could create a constitutional crisis, a situation that could destabilise the country.

How did the murder take place?

Lipolelo was gunned down at close range on the side of a dirt road while returning to her home in a small village on the outskirts of the capital, Maseru.

She was involved in bitter divorce proceedings with Mr Thabane when she was killed.

At the time, the prime minister was living with Maesaiah, 42, as if she were his wife.

But Lipolelo had already won a separate legal battle to be recognised as First Lady, rather than Maesaiah.

Maesaiah accompanied Mr Thabane to his inauguration, following his estranged wife's death.

Two months later she and Mr Thabane got married in a Catholic ceremony held at a packed stadium in Maseru.

She has also been charged with the attempted murder of a family friend Thato Sibolla, who was with Lipolelo at the time of the shooting and is expected to be a key witness in the murder case.

Maesaiah has not yet been asked to enter a plea. (Text, excluding headline, courtesy of BBC)

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