The security cordon in September will centre on The Brighton Centre

Brighton and Hove City Council and Sussex Police hope that by putting the 25 to 29 September date in diaries early people can avoid disruption.

The key feature will be a secure cordon round The Brighton Centre and The Grand and Metropole hotels on the seafront.

The Conservative and Liberal Democrat conferences will be held in Blackpool.

Access arrangements

"Accommodating a party conference in Brighton in the current international climate will involve extensive but vital security measures," said a spokesman for Sussex Police.

"These will not necessarily be identical to those for previous conferences."

Police say the exact arrangements for Operation Otter will be continuously reviewed before September and may be subject to change right up to the event.

"Access arrangements for neighbouring properties during the conference cannot yet be confirmed but details will be communicated as soon as they can," said the spokesman.

Massive security

"It is expected that all neighbouring businesses will operate as normal during the event."

Last year's Labour Party conference in the town involved a massive �2.375m security operation.

The Grand Hotel was the scene of the IRA bombing during the 1984 Conservative Party conference.

The then prime minister, Margaret Thatcher, escaped uninjured, but the blast killed five people and injured 34 others.