The US had also issued a travel advisory for its citizens earlier this week.

The UK's Foreign and Commonwealth Office (FCO) has advised its citizens against travel to Pakistan due to a "high threat of terrorism, kidnap and sectarian violence" throughout the country and said foreigners may be "directly targeted".

"Terrorists are very likely to try to carry out attacks in Pakistan. There's a high threat of terrorism, kidnap and sectarian violence throughout the country, including the cities of Islamabad, Rawalpindi, Lahore and Karachi," the FCO advisory said.

"Protests can take place with little warning and turn violent quickly. You should avoid demonstrations, large crowds of people and public events throughout Pakistan.

"Foreigners, in particular westerners, may be directly targeted. Densely populated unsecured areas like markets, shopping malls, restaurants and places where westerners and the Pakistani elite are known to congregate, are potential focal points for attacks. You should be extra vigilant at all times," it stated.

The UK office also urged its citizens to avoid areas located close to the Line of Control (LoC) due to tensions between India and Pakistan following the February 14 Pulwama suicide attack which killed 40 CRPF troopers.

The FCO further said that the British High Commission's ability to deliver consular assistance, including in an emergency, may be restricted or delayed in certain parts of Pakistan where the federal government does not give permission to travel.

According to the advisory, much of Balochistan, rural Sindh and Khyber-Pakhtunkhwa provinces, including the Federally Administered Tribal Areas and Agencies, Quetta and parts of Sindh have a high level of lawlessness.

The US had also issued a travel advisory for its citizens earlier this week.