London: Britain downgraded its terror threat from critical to severe after the Joint Terrorism and Analysis Centre said the threat was no longer imminent.
The level was initially raised to critical last week when police arrested 23 suspects involved a plot to blow up as many as 10 planes on-route to the US.
"I want to stress that the change in the threat level does not mean that the threat has gone away," Home Secretary John Reid said.
"There is still a very serious threat of an attack. The threat level is at severe, indicating the high likelihood of an attempted terrorist attack at some stage, and I urge the public to remain vigilant," Reid said.
Stringent passenger checks were still in place following the announcement, with a ban on all liquids other than prescription medicines and baby milk.
BAA PLC, which owns Heathrow and other major airports, announced that passengers will be allowed to carry a small bag, no larger than 45cm long by 35cm wide, from Tuesday morning.
