The suit, filed on Wednesday, stipulated that Bolivia sought "to re-establish the rights of a country unjustly shut off and deprived of its maritime attributes for more than 100 years."

Bolivia has been preparing legal, historical and economic arguments for its lawsuit for more than two years.

Bolivian Foreign Minister David Choquehuanca insisted that the action was not an unfriendly act. He said that a 1904 agreement, establishing the current boundaries between Bolivia and Chile was not valid because it had been signed by Bolivia under duress.

"This Bolivian suit requests that the International Court of Justice adjudge and declare that Chile is obliged to negotiate in good faith with Bolivia a prompt and effective accord that grants it a fully sovereign outlet to the Pacific Ocean," said Choquehuanca.

The 1904 "Treaty of Peace and Friendship" followed decades of fighting and discord, precipitated by the 1879-1884 Pacific War between Chile and an allied Peru and Bolivia.

Bolivia, the poorest country in South America, aims to recover some 400 kilometers (250 miles) of coastline that it lost.

Presidential promises

A promise to file an action was made by Bolivian President Evo Morales (pictured above) in March during patriotic "Day of the Sea" commemorations held each year in Bolivia to mark the loss.

However Center-right Chilean President Sebastian Pinera, who faces presidential and parliamentary elections in November, rejected any question of negotiations to alter the current boundaries.

"We will defend with all the might in the world every square meter of our land and every square meter of our sea," said Pinera in response to the suit, vowing that Chile would use "all" instruments within its reach with regard to international law to defend its northern territories.

The Chilean president's words were echoed by former socialist President Michelle Bachelet who said: "The decision of Bolivia to file a suit against the government of Chile in The Hague was a serious mistake in as much as that it [Bolivia] has opted to abandon the path of dialog."

Negotiations were opened in 2006 between Morales and his then counterpart Bachelet, but these were unsuccessful.

rc/kms (AFP, dpa, Reuters)