This article is more than 9 years old

This article is more than 9 years old

Lebanese politicians reacted angrily to a demand by Hezbollah's leader, Hassan Nasrallah, to boycott the tribunal investigating the assassination of the former prime minister, Rafiq al-Hariri.

Nasrallah's demand added to nervousness that if indictments are soon issued in the 2005 murder case it will plunge Lebanon into turmoil. Hizbullah

Hezbollah, a Shia movement backed by Iran and Syria, has accused the UN-supported tribunal in the Netherlandsof acting in the interests of Israel.

It is widely expected that indictments, probably against Hizbullah officials, will be issued before the end of this year.

Nasrallah, sounding grave, issued his call on Thursday night in a broadcast on al-Manar, Hezbollah's TV station, after an incident involving tribunal investigators and women at a clinic in the Shia southern suburbs of Beirut.

"I ask every official and every citizen in Lebanon to boycott those investigators and refrain from co-operating with them … because all that is presented is passed on to the Israelis," he said. "Continued co-operation … helps to desecrate the country and assaults the resistance."

Judge Antonio Cassese, the tribunal's president, said it would "not bow to any act of interference and intimidation in carrying out our mandate in an independent and fair manner".

Lebanese and foreign observers and analysts, already anxious about the tensions of recent weeks, fear Nasrallah's remarks signal a tough new stance on the potentially explosive affair. Hezbollah is part of a fragile coalition government which could fall if the crisis deepens.

Samir Geagea, leader of the Christian Lebanese Forces, called for an emergency cabinet meeting to discuss the matter. "This is a threat to the Lebanese government, as the government is the first to co-operate with the (tribunal) investigators," he told al-Arabiya TV.

Lebanon's current prime minister, Saad Hariri, the son of the murdered man, is visiting London on Monday for talks with David Cameron and Wiliam Hague, the foreign secretary. Britain has said it is doing what it can to help the work of the tribunal and maintain Lebanon's sovereignty and stability.

Saad Hariri originally blamed Syria for his father's death but publicly withdrew the accusation last month as he sought to mend fences with President Bashar al-Assad in Damascus.

The tribunal was set up under UN auspices to investigate the bomb that decimated the former prime minister's motorcade in Beirut in February 2005, killing him and 22 others. Syria was blamed by many for the murders. Damascus denied the accusation but the protests that followed led eventually to the withdrawal of its troops from Lebanon after 29 years.

In recent weeks Syria has denounced the tribunal while a judge issued arrest warrants for Lebanese officials close to Hariri who were accused of having helped provide false testimony to investigators. The US has repeatedly criticised Syria for ignoring Lebanese sovereignty.