Demonstrators as well as Queen Elizabeth II were on hand as the kind of Saudi Arabia started a state visit to the UK.

King Abdullah was welcomed by the queen amid protests on Tuesday, a day after he had accused Britain of failing to address so-called acts of terrorism.

The queen, with her husband, Prince Philip, and Gordon Brown, the British prime minister, met the king at the Horse Guards Parade in central London.

Some politicians will boycott a state banquet hosted by the queen at her official London residence in protest at Saudi Arabia's human rights record.

On Monday, King Abdullah had told the BBC that Britain had failed to act on intelligence from his country which could have stopped suicide bombings in July 2005 in British capital.

The bombings, carried out by four young British Muslims, killed 52 people on the public transport system.

"I believe most countries are not taking this issue too seriously including, unfortunately, Great Britain," King Abdullah said.

His comments have been denied by the MI5, British intelligence agency, and the foreign office.

Angry suspicion

King Abdullah's visit, the first by a Saudi monarch in 20 years, has angered some politicians, protestors because of the country's poor human rights record criticized by groups such as Amnesty International

Saudi Arabia is a British ally in the Middle East, both politically - over Iraq, Iran and counter-terrorism - and commercially as a source of oil and with booming British exports to the kingdom worth $9.1bn last year.

Its commercial links have caused some embarrassment.

Britain's Serious Fraud Office last year investigated a $88.9bn arms deal with Saudi Arabia, but the inquiry was called off on the grounds of national interest in December.

Campaign Against the Arms Trade, a British pressure group, held a demonstration on Tuesday calling for the case to be reopened, during the visiting king's carriage journey with the queen.

King Abdullah is expected to meet Brown on Wednesday to discuss counter-terrorism, Iran, Iraq, Lebanon and the Middle East peace process.

A spokeswoman for Brown said he would "raise issues he believes to be appropriate" with the king.

"The government has, where necessary, raised concerns we have regarding human rights but equally we are recognizing that there have been developments under way," she said

King Abdullah is set to visit Italy, Germany and Turkey after leaving London on Thursday.

PHOTO CAPTION

Abdullah bin Abdul-Aziz