Tunisia's prime minister "regrets" the UK Government's decision to fly its citizens home, as scores of British holidaymakers make the journey back today.

His comments come as Tunisia's interior ministry said counter-terrorism forces had killed five suspected extremists in a mountain gunfight.

Habib Essid told Sky News: "We regret the decision was taken to ask all the citizens to leave the country. We could have done something else that could help both sides, but we understand.

"Tunisia needs to be supported. It needs to be helped against what the terrorists are doing.

"The objective of the terrorist is that people from abroad won't feel safe in Tunisia."

The prime minister, speaking in a parliamentary debate yesterday, said his government did everything in its power to protect British citizens and their interests.

It has carried out 7,000 security operations since a terrorist attack in Tunis in March, and the prime minister said the government was working to remedy "shortcomings".

Yesterday, a gunfight erupted as a special Tunisian national guard unit tracked and chased eight suspected extremists near the town of El Ktar in the Gafsa region.

The Tunisian government declared a state of emergency following the attack which left 30 British tourists dead, and the UK's foreign office has now changed its travel advice for the country - saying that a terrorist attack is "highly likely".

Extra flights have been laid on across the weekend to evacuate up to 3,000 British package holidaymakers and 300 independent travellers who were believed to be in Tunisia.

Foreign Secretary Philip Hammond defended the repatriation of tourists, after protests from the north African country that the UK was playing into terrorists' hands.

Some Britons in Tunisia voiced anger that the Foreign and Commonwealth Office (FCO) had not changed its travel advice to warn against visiting the country immediately after the June 26 attack in the resort of Sousse.

But others said they were disappointed to have to cut their holidays short. Heidi Barlow, 34, said she was reassured by the armed guards posted at hotel entrances and beaches, adding: "People feel safe. They certainly didn't expect to have to leave."

Foreign tourism accounts for around 15% of Tunisian GDP, and the country's ambassador in London, Nabil Ammar, warned: "This is what the terrorists want. By damaging the tourism, by having foreigners leaving the country, they damage the whole sector and put so many people out of work and on the streets.

"One of the sources of terrorism is lack of hope. It is not the only motor of it but it is one of the very important origins."

Mr Hammond said the Government had been careful not to act in a "knee-jerk manner" by urging Britons to quit Tunisia after the Sousse attack, and said the UK will continue to work with Tunisia on improving security and hoped to downgrade the travel advice "in the not too distant future".

Downing Street said that "substantial" work was needed to improve security for tourists, and it was likely to be "some time" before the advice against travel can be lifted.

The first disappointed holidaymakers, who arrived back in the UK at Manchester Airport yesterday, criticised the Government's handling of the issue.

Tracey Caburn returned from Tunisia with her mother, Maureen Sudmore and sister Debbie Murphy, from Pontefract.

Mrs Caburn said: "It's a disgrace. We felt safe. We would've stayed there. We didn't feel threatened at all. There were guards on the roof, the gates, the beach. We wanted to stay.

"If they were going to bring us home so quickly they should not have let us fly out in the first place."

Les Aston, 61, from Shrewsbury, was also disappointed to be home.

He said: "They let us go out there and now we've been brought back home. It makes no sense. The staff were in tears when we left the hotel. Tourism in Tunisia will be ruined."

Downing Street said the revised travel advice was based on information received over the previous 24 hours.

This included evolving intelligence about the threat to Britons in Tunisia; information from the Tunisian security authorities that people with possible links to the Sousse attack were still at large; and the results of a security assessment carried out by UK experts.

A Thomas Cook spokesman said it was "strongly advising" customers in Tunisia to return to the UK over the weekend, and was sending specialist assistance teams to the country to offer additional support in resorts.

Monarch Airlines is arranging to repatriate all customers in resorts "back to the UK as soon as possible".

Tour operators Thomson and First Choice have no remaining customers in the country, but have cancelled all flights to Tunisia for the summer season.