An emergency Cobra meeting is being held on Monday with ministers, police chief and security officials gathering to assess the threat posed by domestic terrorism.
The meeting, to be chaired by Prime Minister Rishi Sunak, also plans to consider intelligence that Iranian agents may be creating unrest in Britain by stoking pro-Palestinian protests, according to reports.
Antisemitic and Islamophobic incidents have surged in Britain since a deadly rampage by Hamas gunmen in Israel on Octover 7 sparked retaliatory attacks on Gaza.
Massive pro-Palestinian demonstrations have been held in London and other major UK cities, while Jewish groups have held vigils for hostages who were taken by the militants.
“We have to make sure that British systems are safe and secure from the threat of terrorism as the government always does,” higher education minister Robert Halfon told Times Radio.
The UK’s MI5 intelligence agency currently regard the threat to the country from terrorism as substantial, meaning an attack is likely.
There are two higher categories of threat level - severe, meaning an attack is highly likely, and critical, meaning an attack is highly likely in the near future.
Foreign Secretary James Cleverly on the weekend urged pro-Palestine supporters to be "conscious of disinformation and manipulation" following reports Iran is attempting to use the rallies to sow division.
It comes as Joe Biden's security adviser suggested Hamas could be preventing British nationals from leaving Gaza.
Jake Sullivan, the White House national security adviser, said Egypt and Israel were prepared to allow foreign nationals to leave Gaza via the Rafah crossing.
But he said the Palestinian militant group Hamas, which rules the bombarded territory, had not agreed to terms that would grant foreigners an opportunity to depart for Egypt and reach safety.
The Rafah crossing between Egypt and Gaza is the only border point in the territory that is not controlled by Tel Aviv.
The throughway into north-east Egypt is likely to be the main exit route for those trapped in Gaza but it is currently closed other than for aid deliveries.
The Prime Minister last week said UK Border Force teams are in Egypt to ensure British nationals can escape from Gaza when the crossing is opened to foreign nationals.
The Foreign Office is in contact with around 200 UK nationals in Gaza, Rishi Sunak has previously said.
Those stuck in Gaza have dealt with communication blackouts, the threat of Israeli air strikes and a lack of food and water after Tel Aviv blockaded essentials in response to Hamas's attack on October 7, raids that killed 1,400 people.
