Armed police are patrolling Tunisia's beach resorts after the government said it would deploy hundreds more inside hotels after Friday's attack in Sousse that left 38 foreigners dead.
After an emergency meeting late on Saturday, Interior Minister Najem Gharsalli promised new steps to ensure the "protection of Tunisia's tourist sites and beaches by armed police units".
"We can no longer refrain from taking difficult measures," Gharsalli said in a statement carried by Mosaique FM radio
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"We don't want to make tourist establishments into barracks, that's not our goal. But we must act to guarantee the security of the tourist sector."
The government also confirmed that it would stop all Tunisian men below the age of 35 from travelling to Libya.
Thousands of tourists have left Tunisia since the attack, which has shocked the North African country that relies heavily on tourism for jobs and foreign currency revenues.
'Further attacks possible'
The British government cautioned on Sunday that further attacks "are possible" in Tunisia.
Interior Minister Theresa May told the BBC there had been no change in the British death toll of 15 dead, in the most signiifcant attack against UK citizens since the 2005 London bombings, but said: "We are expecting that to rise."
In updated travel advice, the UK's foreign ministry urged those who remained in Tunisia to be vigilant and said there was a risk of further incidents.
"Further terrorist attacks in Tunisia, including in tourist resorts, are possible, including by individuals who are unknown to the authorities and whose actions are inspired by terrorist groups via social media," it said.
The British government held meetings of its emergency response committee on Friday and on Saturday, and May was due to chair a third meeting later on Sunday.
In Friday's attack, an armed man disguised as a tourist opened fire on a beach outside two hotels with a weapon he had hidden in an umbrella.
The attacker was later shot by police, taking the death toll including the assailant to 39, with dozens of others injured.
The shooting came the same day as a bombing in Kuwait, which was also claimed by the Islamic State in Iraq and the Levent, and a beheading at a factory in France.
The head was surrounded by two Islamic flags bearing the Shahada, the profession of [the Muslim] faith.
Source: Al Jazeera and agencies