Charges at car parks in Brighton and Hove city centre have been increased without warning.

NCP has ditched the one-hour fee at many car parks and ruled drivers must pay for a minimum two hours.

Visitors complained there was no warning before the price rises and that even after their introduction on Saturday there were no signs advising motorists of the new prices.

At Russell Road, black bin liners had been taped over signs showing the previous charges but there was no indication of the new rates.

Drivers face a minimum charge for two hours at Carlton Hill, High Street and North Road, where NCP has hoisted the lowest charge from 80p for one hour to £1.30 for two hours.

At the Trafalgar Street NCP car park the minimum charge has gone from 90p for one hour to £1.50 for two hours. The one-hour stay will remain at Oxford Court but charges have increased by 10p to 90p.

NCP has also scrapped the one-hour charge at car parks in Russell Road, Church Street and Regency Square, to be replaced with blocks of 15 minutes at 40p each.

For a one-hour stay, or four blocks of 15 minutes, the cost is £1.60, up from £1.20.

The charges increase by 40p for every extra 15 minutes, making a four-hour stay £6.40 compared to the previous rate of £4.70.

Gilbert Went, from Haywards Heath, was shocked to find he owed £6.80 for his four-and-a-half-hour stay at Church Street.

When he questioned the amount, he was directed to a typed A4 piece of paper stuck on a wall.

Mr Went, who was in Brighton with friends to do his Christmas shopping, said: "They've put it up just in time for the Christmas rush. There was no notice telling us it had gone up before we went to pay. It's daylight robbery."

George Kennedy, from Hastings, said: "It's a good idea to have a 15-minute rate but why not also leave the previous hourly rate?"

Graphic designer Sue Scriven, from Tonbridge, Kent, said: "I love the shops in Brighton but I like to park centrally and the charges are very high."

Last month The Argus revealed plans to charge hotel guests £10 to park in the centre.

Richard Baker, general manager at The Grand, said: "They've just sneaked in another price hike at one of the busiest shopping times of the year.

"Stunts like this will drive people out of the city. They will spend their money at out-of-town shopping centres instead."

Roger McArthur, chairman of campaign group Traders Against Parking Persecution, said: "It is already hard enough to park in Brighton, while the parking companies are making a fortune."

An NCP spokesman said the changes were in response to customer requests and would offer drivers more choice.

He said: "On the whole, we believe our customers will save money, especially those just popping into the shops for a short time."

Parking charges at Churchill Square shopping centre, Brighton, remain unchanged.