The leftist government also offered the United States $23-million in "economic aid" for "human rights training" to prevent attacks on people's privacy, torture and extrajudicial executions.

"Ecuador unilaterally and irrevocably renounces these preferential customs tariff rights," Communications Minister Fernando Alvarado said, reading a government statement.

"Ecuador does not accept pressure or threats from anyone, and does not trade on principles or make them contingent on commercial interests, even if those interests are important," he said.

The government of leftist President Rafael Correa said that while it had received the preferential rights in exchange for its cooperation in the war on drugs, they had become a "new instrument of blackmail."

The preferential trade program, which covers key Ecuadoran exports such as fresh-cut roses, fruits , vegetables and tuna, was set to expire on July 31 unless the US Congress renewed it.

The arrangement, which dates back to the early 1990s, originally benefited four Andean nations, and Ecuador was the last country still participating in it.

Lost exports

But analysts have warned that Washington may refuse to renew it if Quito grants asylum to Snowden.

The United States is Ecuador's main trade partner, buying 40% of the Andean nation's exports, or the equivalent of $9-billion per year.

The 30-year-old Snowden, a former National Security Agency contractor who embarrassed the government of US President Barack Obama by revealing details of vast Internet and phone surveillance programs, has requested asylum from Ecuador.

Ecuador has said it could take as little as one day or as long as two months to decide whether to grant asylum to Snowden, who remained on Thursday in the transit area of a Moscow airport after fleeing Hong Kong.

Snowden's exit from Moscow appears complicated, as the United States has revoked his passport and a senior Ecuadoran foreign ministry official denied claims by anti-secrecy website WikiLeaks that Quito had given him a travel document.

Pressure on Equador

​An online publication of the Ecuadoran presidency said Washington has put "explicit and implicit" pressure on Quito over Snowden's asylum petition as well as its decision to shelter WikiLeaks founder Julian Assange at its London embassy and its ties with "nations considered 'enemies' of the United States."

The official publication, El Ciudadano, added that the US embassy has urged Ecuador to hand over Snowden if he sets foot in the Andean nation.

Political Issues Minister Betty Tola meanwhile warned that prosecuting Snowden "could contravene" a regional human rights pact that the United States has not ratified. – AFP