The Liberation Tigers of Tamil Eelam (LTTE) were ready to launch sea-borne attacks against Colombo harbour, which they had failed to attack on at least two previous occasions, the privately-run Sirasa channel said.

"The LTTE has planned to carry out the attack around mid this year," the television channel, said quoting the police Criminal Investigations Department.

The defence ministry's spokesman, Brigadier Prasad Samarasinghe, said he was unaware of the plan. There was also no immediate comment from the guerrillas.

The television report said the Tiger planned to use suicide bombers to storm the port and later destroy containers while carrying out a simultaneous air strike against an oil depot and an electricity generating complex in Colombo.

The Tiger rebels staged a daring air attack on two oil storage facilities in and around the capital in April.

The low-flying light aircraft attack prompted Sri Lankan authorities to shut the island's only international airport at night to prevent flying Tigers using the cover of commercial aircraft to slip into the skies over the capital.

On Tuesday, Tiger rebels came close to cutting off a large chunk of Sri Lanka's electricity supply by setting off a bomb against a key power line, officials said. The explosion only caused minor damage and no one was hurt.

Last week Prime Minister Ratnasiri Wickremanayake also said authorities had information about a truck bomb that could destroy half the city, which is home to 650,000 people.

Sri Lanka has stepped up security in Colombo amid fears of rebel bomb attacks and last week evicted nearly 400 ethnic minority Tamils from the city, saying they were a threat to national security.

However, the move was halted by the Supreme Court amid allegations that the eviction was illegal and a form of "collective punishment" on the Tamil community for the actions of the Tiger guerrillas.

Meanwhile, Sri Lanka's top defence official has accused Western nations of bullying his government over human rights and defended the eviction of ethnic Tamils from the capital, a report said Wednesday.

Defence Secretary Gotabhaya Rajapakse also rejected warnings from Britain that the former colony risked international isolation over the deteriorating rights situation in the island.

"Britain, or Western countries, the EU (European Union) countries, they can do whatever," Rajapakse said in an interview with the BBC. "We don't depend on them ... they are not giving anything."

His move to evict nearly 400 ethnic minority Tamils from the capital was halted by the Supreme Court amid an avalanche of condemnation by local and foreign human rights groups.

The country's prime minister on Sunday expressed regret over the expulsions, promised it will not happen again and apologised to the Tamils after promising a disciplinary action against officials responsible for excesses.

The defence secretary, however, defended the action -- aimed at preventing Tamil Tiger rebels from infiltrating the capital -- and lambasted foreign governments, which condemned the Tamil evictions.