Colleagues and reporters were unable to contact Mr Riot for a second straight day, further stoking speculation that he wanted out of the Barisan Nasional after not getting a spot in the new Cabinet.

An ethnic Bidayuh, he is a member of Sarawak United People's Party (SUPP), one of the BN's 14 component parties.

Yesterday, SUPP Publicity Secretary Alfred Yap Chin Loi told reporters that the elusive MP would meet Prime Minister Abdullah Badawi today.

Mr Yap also said that there was no question of Mr Riot wanting to leave BN. 'To date, we have not received any resignation letter from Richard, so it is not true.'

The fear is that Mr Riot's departure from the coalition could snowball, leading to the collapse of the federal BN-led government. Indeed, the rumour mill yesterday reported that another Sarawak MP, Mr Tiki Lafe, may quit BN.

When asked point blank if that was true by Malaysiakini's online newspaper, he replied: 'I am not saying anything.'

Mr Lafe, also a Bidayuh, is from another small BN party, the Sarawak Progressive Democratic Party.

One person who said he managed to speak to Mr Riot yesterday was SUPP chief George Chan. Mr Riot had pledged his support for the BN and was only on holiday in Kuala Lumpur, he said in a statement.

The concern about possible defections from BN began after the March 8 general election.

While the BN won 140 seats, the other 82 constituencies were won by the opposition coalition.

The opposition's de facto leader Anwar Ibrahim raised alarm bells in the BN when he said on Monday that he had been approached by members of BN coalition partners in Sarawak, Sabah and elsewhere who wanted to defect.

The BN itself has acknowledged that Datuk Seri Anwar is working behind the scenes to rope in at least 30 BN MPs.

If he succeeds, the BN would be left with 110 seats and the opposition coalition with 112 seats - enough to form a new federal government.

The fears in BN are not without precedent. In February 1994, the opposition Parti Bersatu Sabah (PBS) won the elections for the fourth term. It had 25 seats in the Sabah legislative assembly, to 23 won by the BN.

But the PBS state government lasted only two weeks. So many of its assemblymen crossed over to the BN that by April, the PBS had only three seats left in the assembly. The BN has run the Borneo state ever since.

The crossovers were widely blamed on the use of cash in an alleged BN scheme orchestrated by Datuk Seri Anwar himself, who was then one of the rising stars in the BN's leading party, Umno.

There is no law to prevent elected representatives from switching political parties, says constitutional law expert Professor Shad Faruqi.

'It gives the impression the politician has lied to the electorate,' he was quoted as saying by the New Straits Times newspaper yesterday. 'Malaysia would do well to have an anti-party hopping law.'

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