Britain's terror threat level was reduced on Wednesday night from "critical" to "severe" after no intelligence suggest any imminent danger.

Home Secretary Jacqui Smith made the announcement after eight major suspected had been arrested over the London and Glasgow bomb attacks, the British Broadcasting Corporation (BBC) reported on Wednesday.

The domestic security services (MI5) and the Joint Terrorism Analysis Center both said an attack is no longer expected imminently.

The announcement will likely be followed with a slight reduction in security procedures and controls. But Prime Minister Gordon Brown said at the Parliament in the afternoon that more background checks will be conducted on skilled migrant workers in the country.

He also ordered an urgent review of National Health Service recruitment now that all suspects detained have links to the medical service.

Brown also wants the world to see Britain will "stand strong, steadfast and united in the face of terror."

Britain will sign new agreements with countries around the world to ensure a coordinated response to the terror threat, he noted.