Government websites managed to hold up last night, despite a sustained attack from hackers defending Wikileaks founder Julian Assange.
A code designed to overload the Ministry of Justice, Downing Street, Home Office and Department of Work and Pensions websites was spread on Twitter using several hashtags, including #OpFreeAssange.
The software attack was announced with the words "Tango Down".
By triggering 1,000 service requests per second the attacks were designed to bring the sites down, but most were able to withstand the assault. Some users of the Ministry of Justice website may have experienced disruption.
Some of the activists came from the UK but most appeared to be from across the world, including the US, Brazil and Chile.
Meanwhile, Britain was told it would be committing "diplomatic suicide" if it tried to enter Ecuador's embassy, the country's president warned.
The development comes as relations between the UK and Latin American states – already tense due to the Falklands Islands dispute – deteriorate as a result of the Assange row.
A meeting of the Union of South American Nations (Unasur) earlier this week saw Ecuador's foreign minister hold hands with the his counterparts from several regional states as they berated Britain for its threat to use a little-known piece of legislation to enter the embassy.
The left-leaning Organisation of American States is set to meet on Friday and offer strong support to Ecuador.
"While the United Kingdom hasn't retracted nor apologised, the danger still exists," President Rafael Correa said.
Such a course of action would be "suicide for Great Britain because then people could enter their diplomatic premises all around the world and they wouldn't be able to say a thing".
The Ecuadorian leader said that in addition to the Organisation of American States he could also take the case to the United Nations.
"Remember that David beat Goliath. And with many Davids it's easier to bring down a number of Goliaths," he said.
"So we're hoping for clear and coherent backing because this violates all inter-American law, all international law, the Vienna Convention and all diplomatic traditions of the last, at least, 300 years on a global scale."
He added: "The British say they have no choice but to extradite him but why didn't they extradite Augusto Pinochet?"
The Foreign Office's decision to tell Ecuador it could use the Diplomatic and Consular Premises Act 1987 to enter the embassy has spectacularly backfired.
Even though any use of the act would require a lengthy court case, complete with appeal processes, the suggestion Britain could enter the embassy allowed Ecuador to gather regional support and present the Assange row as an instance of western bullying against developing states.
The political row is a major setback for the Foreign Office, which has dedicated considerable resources to improving relations with Latin America, as part of a move to decrease reliance on trade with the eurozone.
Foreign secretary William Hague is coming under pressure to cancel Britain's £60,000 a year aid package to Ecuador, which has seen the UK spend £3.3 million on the South American state between 2000 and 2010.
There are also complaints about the £50,000 a day policing costs of making sure Assange is not smuggled out the embassy.