The ceasefire in the hill-ringed Kathmandu valley was aimed at "creating an easy atmosphere for the people to participate in the peaceful protest movement" against the king, Himalkhabar.com, an online news service, quoted Maoist chief Prachanda as saying.Nepal's seven main political parties have called a four-day nationwide general strike from Thursday, to be followed by a series of protests and a big rally in Kathmandu on April 8, in a bid to pressure King Gyanendra to restore democracy.

The government has vowed to halt the protests, saying Maoist rebels could infiltrate rallies and create unrest.

The political parties feared that the government could use this as a reason to crack down on their demonstrations and had appealed to the guerrillas to announce a truce.

Prachanda's announcement came hours after Nepali police fired tear gas shells to break up protests by students in the capital against the king, who seized power last year.

About three dozen students burned tyres on Kathmandu's roads and threw rocks at police in front of a college campus near the royal palace as they demonstrated against the king's rule, witnesses said.

"This is for the restoration of democracy," said activist Kamal Basnet, carrying a mobile phone in one hand and a brick in the other. "We don't want an autocratic monarchy."

Demonstrations have become an almost daily affair in Nepal's temple-studded capital, with hundreds and sometimes thousands of people chanting slogans against the king.

King Gyanendra says he was forced to take power in February 2005 after political parties failed to quell a Maoist revolt in which more than 13,000 people have been killed since 1996.

The Maoists want to topple the monarchy and set up a single party communist republic in one of the world's 10 poorest countries, which is tucked between giants China and India.