British Foreign Secretary William Hague says Britain will not allow WikiLeaks founder Julian Assange safe passage out of the country and is determined to extradite him to Sweden.
Hague said Ecuador's decision to give Assange asylum should not be used as a way for him to escape the legal process.
"It does not change the fundamentals of the case. We will not allow Mr. Assange safe passage out of the United Kingdom, nor is there any legal basis for us to do so," Hague said. "The United Kingdom does not accept the principle of diplomatic asylum. It is a far from universally accepted concept."
Assange sought refuge in the Ecuadorean Embassy in London two months ago to avoid extradition to Sweden where he is wanted for questioning over sexual assault charges.
Ecuador's Foreign Minister Ricardo Patino announced on August 16 Ecuador was granting Assange asylum as it feared for the safety and rights of the WikiLeaks founder.
Assange denies the sexual assault allegations and says he fears he would be handed over to the United States where he could face espionage charges for posting thousands of leaked U.S. diplomatic cables in 2010.
Britain's Hague said the case had nothing to do with Assange's activities at WikiLeaks. He said Britain was determined to carry out its legal obligation to extradite Assange to Sweden.
"We are disappointed by the statement by Ecuador's foreign minister today that Ecuador has offered political asylum to Julian Assange," Hague said. "Under our law, with Mr. Assange having exhausted all options of appeal, the British authorities are under a binding obligation to extradite him to Sweden. We must carry out that obligation and, of course, we fully intend to do so."
He also rejected the Ecuadorean claim that Britain had made what he called "threats" in case Ecuador decided to give Assange assylum.
Demonstrators hold a sign reading "We are sovereign, not colonies," as they shout slogans outside the British Embassy in Quito on August 15.
He said Britain was committed to "amicably" resolve the matter but added he expected it would take considerable time.
"There are no time limits. As I say, I think that is a problem more for the embassy and for Mr. Assange than for this country, except that we are determined to fulfill our legal obligations under the extradition act to Sweden," Hague said.
In Washington, State Department Victoria Nuland declined comment on Ecuador's decision.
Asked about WikiLeaks' assertions that the United States was seeking him, she said she had "no information to indicate that there is any truth to that at all."
Earlier on August 16, Sweden rejected accusations it was not prepared to give Assange a fair trial.
The Swedish Foreign Ministry summoned Ecuador's ambassador over the decision to grant Assange asylum which it said was "unacceptable."
Assange, speaking at the Ecuadorean Embassy in London, said Ecuador's decision was "a significant victory" for himself, and for WikiLeaks.
With reporting by AFP and AP