Tunisia’s state of emergency has been extended by seven months.
The country was first placed on alert in November 2015 following a suicide attack on a police bus.
This came months after 38 people - including 30 British holidaymakers - were gunned down on a beach in the tourist resort of Sousse.
The state of emergency has been extended a number of times since then, most recently on Monday (March 12).
The Foreign Office (FCO) on Thursday (March 14) issued fresh travel advice for Tunisia.
It said since the Sousse attack, the government had been working with authorities in Tunisia to investigate the wider threat posed by terrorist groups - and stressed security measures in major cities and tourist resorts had been improved.
However, the FCO has warned terrorists were still “very likely” to try to carry out attacks in Tunisia.
Charter flights from the UK resumed last month, the first for nearly three years. Both Thomas Cook and Tui have relaunched their Tunisia programmes.
Visitors are advised to be “vigilant at all times”, and follow the advice of local authorities and travel operators.
The FCO added there was a “heightened risk” of terrorism against aviation.
Passengers should be aware of additional security measures relating to electronic devices aboard aircraft.
Anyone flying to Tunisia, or transiting through the country, should note FCO guidance on aviation security or contact their airline or travel company for further information.