A Filipino sailor has been sentenced to death in Malaysia for drug trafficking after the court rejected his plea for mercy, local media reported.

Nelson Tanoja Diana, 50, was found guilty of trafficking in 508.6 grammes of cocaine after being arrested at Kuala Lumpur International Airport on Aug 22, 2002 while on his way from Amsterdam to Bangkok.

At his trial on Wednesday, Diana told the judge through an interpreter: "I know you have to follow the law but I have never done this before. I have a big responsibility to my children and for my children's sake I beg for leniency."

High Court judge KN Segara said, however: "Most unfortunate. There is only one punishment for this offence and that is the death sentence."

The death penalty is mandatory for drug trafficking in Malaysia. The sentence is carried out by hanging.

The judge said Diana had admitted he was aware he was carrying the drugs, the New Straits Times reported.

"All the way from Amsterdam to Malaysia you held on very carefully to the bag and landed in Malaysia with a view to taking it to Thailand.

"That in law is already an offence, even though you were going to deliver it in Bangkok," the judge said.

The Philippine embassy in Kuala Lumpur would "exhaust all legal remedies," to help Diana, the country's foreign department said Friday.

The case would be taken to the Malaysian Court of Appeals with the embassy ensuring that Diana's rights were protected and that he was given all consular assistance, the department said in a statement.