KUALA LUMPUR - Jailed Malaysian ex-premier Najib Razak was over the weekend denied his request to be hospitalised for stomach ulcers, followed by a blow from the Selangor palace on Monday to withdrew titles it had accorded him and his wife Rosmah Mansor.

Najib's daughter Nooryana Najwa Najib wrote in an Instagram post on Monday that her father has suffered from ulcers for about 15 years, and "the doctor discovered multiple new ulcers in his stomach" during a scope last Saturday.

The doctors at Kuala Lumpur Hospital (HKL) also did a biopsy which led to some bleeding and the ulcer had to be clipped to stop the bleeding, she said.

She added that her father had requested to be kept at the hospital for observation but was instead discharged by the doctor.

Najib was sent back to Kajang prison, where he is serving a 12-year jail sentence for graft related to the 1MDB financial scandal.

He attended court on Monday, where he is on trial for bribery involving RM2.28 billion (S$708 million) from 1MDB funds and money laundering.

Ms Nooryana also claimed that the doctors had changed Najib's medication from his usual ones, and that a check this morning showed that Najib's blood pressure was "dangerously high, potentially due to the change in medication administered".

"On humanitarian grounds, our family pleads with the prison authority, the hospital and Ismail Sabri's government to do the right thing and allow for dad to receive proper medical care and observation," she wrote.

Health director-general Noor Hisham Abdullah on Monday said that the check-up and procedure had been carried out by senior consultants comprising the heads of the clinical services in their respective fields.

The hospital had held two conferences with Najib and his family members to inform them of the test results.

"They were also informed about the unanimous decision by the consultants that he would be discharged," said Tan Sri Noor Hisham, adding that the medication prescribed to Najib were the same ones he had been taking previously.

"He was healthy before he was allowed to be discharged from HKL."

The Selangor palace has revoked the Datuk Seri and Datin Seri titles that were conferred on Najib and Rosmah, who have been convicted of corruption.

They were similarly stripped of those titles by the Negeri Sembilan palace in 2018, but retain numerous Datuk Seri titles from other states.

Sultan of Selangor Sharafuddin Idris Shah also said that royal pardons cannot be given easily.

"The Judiciary is the last bastion that must be defended to ensure the administration of justice is carried out effectively," he said.

Sultan Sharafuddin added that he was in support of King Abdullah Ahmad Shah's speech last Monday on prerogative powers related to royal pardons which cannot be practised arbitrarily for the benefit of certain quarters.

"The people will have to understand that the pardoning process has to be implemented in line with the laws and procedure provided under the Constitution and laws related to it," he was quoted as saying by The Star daily.

Najib is currently serving 12 years after Malaysia's Federal Court on Aug 23 upheld a July 2020 High Court jail sentence and fine of RM210 million for his role in a case involving a former subsidiary of the 1MDB state fund.

On Sept 1, Rosmah was also convicted of corruption by the High Court for soliciting bribes in return for helping a solar energy firm secure a lucrative contract for hundreds of schools in Sarawak.

She was sentenced to 10 years in prison and a record RM970 million in fines. But she remains out on bail while she makes her appeal at the Court of Appeal.