The leader of Bahrain's largest Shi'ite Muslim opposition party called on youths to refrain from violence in protests ahead of the February 14 anniversary of a revolt crushed by military force.

Clashes between Shi'ite youths and police have escalated in recent weeks, with teenagers throwing petrol bombs and iron bars, drawing accusations from pro-government figures that the opposition is using violence to wrest political concessions.

The repression has led some to respond and throw petrol bombs in the last month, and here I direct a call... that we must continue using peaceful methods, Sheikh Ali Salman told a crowd of several thousand people outside Manama late on Sunday.

Believe me, our case is not throwing petrol bombs... We should not be dragged through that door ... We should stick to our right to protest anywhere and any time. Don't be dragged into violent action.

Inspired by uprisings in Egypt and Tunisia, Bahrainis -- mainly from the Shi'ite majority -- took to the streets on February 14, 2011 to demand democratic reforms. But the Sunni Muslim-led government crushed the protests a month later after talks involving Wefaq went nowhere and sectarian violence spread.

Wefaq and other opposition parties, including the secular Waad, want constitutional changes that would give the elected chamber of parliament the authority to form governments.

The government, dominated by the Sunni Al Khalifa family, has given parliament some more powers of scrutiny over ministers and budgets but not moved on the bigger opposition demands.

Salman said the results of any new dialogue should be followed by a referendum or election of a constituent assembly that would write a new constitution.

Some who listened to the speech said it was unlikely youths who clash with police would heed Salman's call.

I don't think a lot of youngsters will pay attention to that until they see results, said Mohammed Hassan.

Although Wefaq is the biggest opposition force, it vies for influence in the Shi'ite street with youth activists who organise unauthorised protests, and with some leaders who are in prison and do not support the monarchy.

The Gulf Arab state has geo-political importance as home to the U.S. Fifth Fleet, and it is a key ally of Saudi Arabia.

(Writing by Andrew Hammond)