The Malaysian diplomat who is supposed to be flown back to Wellington on Monday to face burglary and sex charge, may not be able to travel just yet as doctors have ordered for more psychiatric tests.

The New Zealand Herald reported that a senior doctor at the Tuanku Mizan Military Hospital where Second Warrant Officer Muhammad Rizalman Ismail was admitted into since Tuesday told the newspaper that Rizalman was "not looking good" and might need further tests.

The doctor said the 38-year-old Muhammad Rizalman seemed withdrawn and depressed.

The diplomat faced charges of burglary and assault with intent to commit rape after he was arrested for allegedly following a 21-year-old woman from a bus stop to her house and attacking her on May 9.

The father of three was said to have broken into her house and undressed but the woman had allegedly fought off Muhammad Rizalman and neighbours had gone to her aid.

He was charged in court on May 10 but claiming diplomatic immunity, Muhammad Rizalman was brought back to Malaysia in the same month.

New Zealand Prime Minister John Key had expressed his preference for the diplomat to be tried under New Zealand's law but Malaysian Foreign Minister Datuk Seri Anifah Aman has insisted for the accused to be investigated here first. A Mindef board of inquiry has been established for the probe.

However, the government later agreed to send Muhammad Rizalman back to face the charges. He would be accompanied by a senior military officer from the Defence Ministry.

Wisma Putra in a statement said Malaysia has complete faith in the New Zealand legal system and has full confidence that Muhammad Rizalman will be given fair treatment with dignity as provided under the law.