Bolivian President Carlos Mesa said late Monday that he would submit resignation to the congress after mass anti-government protests paralyzed the country's capital of La Paz, according to reports from the city.

"It is my responsibility to say that this is as far as it can go," Mesa said on national television. "I have taken the decision to present my resignation from the presidency."

Mesa's decision came hours after tens of thousands of Indians, miners and labor protesters paralyzed La Paz in their largest anti-government march in weeks demanding nationalization of the country's natural gas sector and early elections.

Protesters marched through La Paz waving "Nationalize Now" and "The People Demand Nationalization" banners, and vowed to maintain roadblocks which have caused gas and food shortages in the capital after more than two weeks of blockades.

A senior government official said earlier on Monday that it is "very difficult" for the government and the president to continue in office if "insecurity and instability" continue in the country amid mass street protests.

If the social chaos and insecurity continue, "without a doubt it is very difficult that the president and the government can continue," said Minister of Presidency Jose Antonio Galindo. "We are on the verge of collapse."

Church leaders had called for a truce to help negotiate a solution to the stalemate. They held a second day of talks on Monday as some members of the congress suggested early general elections as the best way out for Mesa.

Earlier on Monday, the embattled president managed to flee his office after protesters threatened to storm the presidential palace.

The recent unrest began after the congress passed a law on May 17 to levy a 50-percent tax on foreign oil and gas companies operating in the country, which has the second-largest gas reserves in South America after Venezuela.

The opposition first demanded higher taxes on foreign firms and later the nationalization of the country's lucrative oil and gas industry.

They also demanded the resignation of Mesa and a rewriting of the constitution to boost indigenous representation in the congress.

Demonstrations have escalated into riots since May 24 when demonstrators blocked a downtown square in La Paz, where the executive and legislative branches are located, and began to smash windows in buildings and cars in the surrounding streets.

The long-term crisis over the gas issue already forced Mesa's predecessor, Gonzalo Sanchez de Lozada, to step down 20 months ago.

(Xinhua News Agency June 7, 2005)