Supporters of the Muslim Brotherhood shout slogans against the Egyptian military and interior ministry. Photo: Reuters

It would be foolish for tourists to remain in Egypt following the ultimatum issued by a militant Islamist group, Foreign Minister George Vella said.

The Sinai-based Ansar Bayt al-Maqdis has threatened to attack any tourist who remains in the country after today.

Last Sunday, two South Korean visitors and an Egyptian were killed in a suicide attack on a bus in Sinai that was claimed by the same group.

“Militant groups like Ansar Bayt al-Maqdis are not to be taken lightly,” Dr Vella told Times of Malta.

“It would be foolish if someone heard this warning and decided to be hard-headed and just stay there.”

Dr Vella felt vindicated for deciding last November to warn Maltese nationals against all but essential travel to all parts of Egypt.

“We had some pressure some time ago to relax the warning for Sinai, because this is a lucrative tourist place, but I dug in my heels and said ‘no way’.

“I didn’t give in; I insisted on all but essential travel [to the entire country],” Dr Vella said.

The Embassy of Malta in Cairo has the contact details of 90 to 100 Maltese citizens who are known to habitually reside in Egypt. Dr Vella said Ambassador George Cassar was making preparations to contact them all should the need arise.

“I don’t want to be alarmist. We cannot answer for all the people who are there.

“They know their own environment, they know the company and locality they are in, and they have to make their own calculations,” he said, adding that he was not aware of any Maltese tourists visiting at this time.

Islamist militants have killed hundreds of policemen and soldiers since the army deposed Muslim Brotherhood president Mohamed Morsi seven months ago.

There are fears that Sunday’s attack on a bus carrying foreigners marks a tactical shift to soft targets that could devastate an economy heavily dependent on tourism.

Now that the Muslim Brotherhood has been outlawed, Dr Vella was concerned that pockets of even more “radical” resistance were growing in strength with unknown consequences.

“No one is quite sure of the size of their web and the contacts they have, and where and when they could strike next. It would be foolish for someone to risk staying unless they are compelled to do so,” he said.

Sunday’s attack revived memories of an Islamist insurgency in the 1990s which included a 1997 massacre at Luxor, when 58 foreign tourists and four Egyptians were killed.

We had pressure some time ago to relax the warning for Sinai... but I dug in my heels

Reuben Vella Bray, marketing director of Sullivan & Sullivan travel agents, said demand for holidays in Egypt had failed to recover since the uprising against former dictator Hosni Mubarak began in January 2011.

“We are not sending people there as we feel it is not safe.

“It is a pity that a country so full of history is losing out,” he said.

The country has struggled to build a functioning democracy in the wake of Mubarak’s resignation in February 2011.

An interim military-led government seized power last July amid widespread protests against the ruling Muslim Brotherhood.

Presidential elections scheduled for this year are widely expected to be won by Field Marshal Abdel-Fattah El-Sisi, the armed forces chief who has led the crackdown on Islamists.