Nicholas Witchell: "The situation British officials had feared"

Before his detention, Anwar Ibrahim defied police restrictions to lead a rally close to the cathedral in central Kuala Lumpur where the Queen had been attending a service.

Later there were clashes outside the prime minister Dr Mahathir Mohamad's residence where police used tear gas to break up a crowd of around 10,000 people.

Pro-Anwar demonstrators have been calling for reform

Police then moved in to detain Anwar, who was sacked as deputy prime minister and finance minister on 2 September.

He has since faced accusations ranging from sexual misconduct to treason, all of which he says are part of a political conspiracy.

Correspondent Harry Peart in Kuala Lumpur: "This was a step too far"

The Queen's visit has also been marred by news of the death of the Duchess of York's mother Susan Barrantes.

She died in a car crash near her home in Argentina on Saturday.

Foreign Secretary Robin Cook is delaying his departure to stay with the Queen.

He had intended to leave the state visit tomorrow night to fly to New York for an important meeting of the United Nations General Assembly.

BBC correspondent Clarence Mitchell reports on the Queen's schedule in Malaysia

But after consulting Buckingham Palace officials, Mr Cook decided to remain with the Queen to advise and support her.

A Foreign Office spokesman said: "Having heard there was a planned rally at the first event on the Queen's visit, Mr Cook decided his priority was to be with the Queen for the rest of the tour.

"This is the right place to be."

Greeting churchgoers at the cathedral

Mr Cook would now arrive at the UN in New York on Thursday instead of Tuesday as originally planned.

The first two days of the royal party's trip is focused around the Commonwealth Games.

The Queen will meet athletes, present medals and then perform the closing ceremony on Monday.

Mr Anwar was arrested at his suburban home hours after the demonstration outside Dr Mahathir's home.

The former minister had expressed confidence that he would not be arrested during the Queen's visit but it appears the march was too much of a provocation for the authorities.

Armed police led him away as about 2,000 supporters shouted "Reformasi" (Reform) and "Long Live Anwar".

Anwar Ibrahim: Called for prime minister's resignation

About 100 riot police with shields and batons surrounded the van before it drove away with Anwar inside.

Dr Mahathir has played down the row, saying the conflict had been a "minor distraction" to the staging of the Commonwealth Games.

The Malaysian authorities are reported to have sentenced two men, including Mr Anwar's adopted brother, to six months in jail for consenting to sodomy with the former minister.