Britain on Friday urged tourists visiting the Red Sea resort of Hurghada to stay in their hotels following a warning by Egyptian police in the wake of violent clashes this week.
The Foreign Office had until now excluded resorts such as Hurghada and Sharm el-Sheikh from its advice against all but essential travel to Egypt because of the political unrest.
But it said one man was killed in Hurghada on Wednesday as violence swept the country following a crackdown on protests by supporters of ousted Islamist president Mohamed Morsi.
Although the violence in Hurghada was away from the tourist districts, the Foreign Office said that "Hurghada police advised tourists to remain in hotel grounds. We advise you to follow their advice".
"You are strongly advised to avoid all demonstrations and large gatherings.
"If you become aware of any nearby protests, leave the area immediately. Do not attempt to cross road blocks erected by the security forces or protestors," it added in a statement.
The Foreign Office does not keep a record of the number of Britons in Egypt but tour operators Thomson and First Choice said they have 11,769 British holidaymakers in the country.
Many of these are in Sharm el-Sheikh, an eight-hour drive from Cairo which a spokeswoman for the two companies insisted remained unaffected by the violence.
"There have been no related incidents in Sharm el-Sheikh or any of the other popular Red Sea tourist areas," she said.
"Like much of Egypt, Sharm el Sheikh was subject to an evening curfew until 6:00 am yesterday morning. This has now been lifted and all our excursions in the Red Sea resorts will resume from today."