Security arrangements for this week's Liberal Democrat conference will be a far cry from the £4 million ring of steel thrown up for last year's Labour Party event.

More than 1,000 police and staff from across the country were involved in the biggest security operation ever mounted in Brighton and Hove last September.

Road and pavement closures were in place 12 days before the event as giant concrete barriers were installed outside the Brighton Centre.

Police were granted unprecedented stop-and-search powers as fears ran high in the aftermath of the July 7 London bombings.

A secure island was created encompassing the Brighton Centre, The Grand Hotel, the Russell Road NCP car park and the Hilton Brighton Metropole Hotel.

Delegates were filtered into lines for bag searches and credentials checking. An air exclusion zone banned aircraft from the area while the Royal Navy patrolled off Brighton.

Police said there would be no road closures for the Lib Dem event and security would be low key in comparison.

Instead, only a handful of officers will patrol the Brighton Centre, which will be manned by security staff and party volunteers.

Despite the muted security arrangements, the Liberal Democrats are predicting that the event, which runs from Saturday until Thursday, September 21, will be the party's biggest ever conference, with 5,000 delegates expected to attend.

Guest speakers will include Lord Coe, chairman of the London 2012 Olympic Games, on the Wednesday, and Gregory Yavlinsky, leader of the Lib Dems' Russian sister party Yabloko, on the Thursday. Leader Ming Campbell will launch the party's new environmental policies, while ex-leader Charles Kennedy will address the conference on Tuesday.

A senior Brighton Liberal Democrat source said: "There won't be as much security but it's not a contest.

"There were good reasons for the ring of steel last year but do we really want that in our city on a regular basis?

"It was very disruptive, of enormous cost to the taxpayer and created an atmosphere of tension.

"We're very much looking forward to an enjoyable conference, which will benefit the entire city."