Protesters in Egypt are to hold a “march of a million people”, calling for President Hosni Mubarak to stand down.
The escalation comes with the British government leading calls for an “orderly transition” to free and fair elections.
The Egyptian army has said it will not use force against protesters, but Britons yet to leave the crisis-stricken country were advised to stay away from public gatherings.
The Foreign Office said: “A major demonstration is planned for February 1 with calls for one million people to take part in central Cairo.
“Similar, although smaller, demonstrations are expected in other major cities around Egypt. British nationals should observe instructions and advice by local security authorities and avoid public gatherings and disturbances.”
After EU talks in Brussels with foreign ministers on Monday night, Foreign Secretary William Hague said: “We are seeking the orderly transition to a broad-based government of free and fair elections, and I think these conclusions are part of a very clear message from EU nations – a message to the Egyptian regime to get on with it and satisfy the aspirations of their own people.”
He said the EU was not interfering in political arguments within Egypt, but acknowledged there was a danger that anything other than an “orderly” transition at the top could mean more dictatorship, rather than more democracy, saying: “There is a risk of extremist politics taking a greater hold, with a more authoritarian system being adopted.
“It is an urgent matter to get on with an orderly transition, so this situation is fraught with danger for Egypt, for the people of Egypt, for the stability of the region and the whole Middle East peace process.”
Ultimately Europe had to rely on democracy emerging in Egypt, without imposing it, he said, adding: “We must to continue to take a robust stance. We have put our faith in democracy – if we believe in democracy, then we must let the Egyptian people decide about that.”
Prime Minister David Cameron told the president by phone on Monday that any attempt to repress mounting public demonstrations – continuing in defiance of a centrally-imposed curfew – would “end badly”.