The protesters marched peacefully through Bangkok's historic district, wearing yellow headbands in honor of Thailand's revered King Bhumibol Adulyadej while carrying banners reading "Junta get out!"

The marchers wanted to end their protest outside the home of Prem Tinasulanond, the king's top royal adviser who has been accused by Thaksin's allies of masterminding the coup last September.

But 2,000 unarmed police blocked the road about 200 metres (220 yards) from Prem's home.

"We cannot allow them to approach his house because someone could try to cause trouble," Manit Wongsomboon, a police major general, told AFP.

Thaksin's allies have staged nightly protests since late May to demand that the junta step down and that elections be held immediately. Sunday's demonstration was the largest in two weeks.

Army-installed Prime Minister Surayud Chulanont earlier Sunday cast doubt on whether elections would be held as promised by the end of the year. Just two weeks ago he had suggested that polls could be held in November.