More traders are being urged to open on Sundays in Bradford to make it a bustling centre seven days a week.

All new tenants in the Kirkgate centre are being asked to sign up to Sunday opening, and the district's market traders are being polled by the Council for their views on all-week trading.

Newcomers Wilkinson's, in the new Rawson Quarter, and North Parade department store Boyes both open on Sundays, but many of the big High Street stores don't, even though their counterparts in Leeds do.

Today Councillor Simon Cooke, chairman of the city centre steering group, asked more traders to consider opening their doors on a Sunday.

Coun Cooke, who is also the Council's executive member for regeneration, said: "No city which makes Sunday a leisure day while others stay open is doing itself a favour.

"I would like to see other shops join in. We are also at a very early stage of discussing it with our market tenants, but it is something which is becoming very important."

Secretary of Bradford Chamber of Trade, Val Summerscales, said: "The more shops which open on a Sunday, the merrier."

But, she said, it could be difficult for small shops to get staff. She said: "We don't want trade to go out of Bradford and the more shops which do it, the more the area is enhanced."

Consumer minister and Bradford South MP Gerry Sutcliffe said stores which take up the Sunday challenge might be pleasantly surprised.

He said: "This is a good initiative but traders should be asked what their thoughts are and not told and, if they think it is good for business and the employees want it, they should go ahead. If they do, I think they will find business will increase."

Bill McCormack, operations manager at the Kirkgate Centre, said Bank Fashions which was due to move into the centre next month would open on Sunday under the new rule. Nineteen of the centre's 60 shops now opened seven days a week.

He said: "Our aim is to make Bradford a Sunday shopping venue.

"The first Sunday openings in the centre were about a year ago and trade has built up. It isn't the same level on Sundays as other days of the week but other centres which have done it have the same experience."

Leader of Bradford Liberal Democrats, Councillor Jeanette Sunderland, said: "Shopping has become a leisure activity for some people and it is foolish not to tap into these markets. Anything that can encourage that habit is to be welcomed."

However Councillor Dave Green, deputy leader of Bradford's Labour group, sounded a note of caution. He said: "Shops will make a financial decision based on their experiences in Bradford. You cannot force them to open if they don't think they have got the trade - what you do is improve the overall shopping offer, which is happening in Broadway.

"If you intend for people to come and shop on a Sunday, you need to have a good shopping offer. In Bradford we may not be there yet, but we are getting there."

Among the key High Street stores which close on Sundays in Bradford is Marks & Spencer although its stores in Pudsey and Leeds city centre open.

Manager Dan Walsh said the Bradford store would open on a Sunday over the four-week Christmas period but would not like to take the risk of permanent Sunday opening.

He said they had in the past extended the shopping week for six weeks at Christmas but had cut it to four because of lack of trade.

Near neighbour Top Shop also closes in Bradford on Sunday but stays open in Leeds.

A store spokesman said: "We tried opening on Sundays in Bradford city centre but unfortunately it just wasn't worth it because we weren't taking any money.

"If it became busier we would definitely open again. If the whole of Bradford's city centre shops opened I think this would happen."

JD Sports opens both its Forster Square Retail Park outlet and its Kirkgate store, but found a big difference in the level of trade.

A store spokesman said: "Our store in the city centre only takes about £300 on a Sunday, normally it would take that within an hour.

"We are busy in the retail park seven days a week because people know we are open. If more shops opened in the city centre our Bradford store would be busier."

But Councillor Martin Love, the leader of Bradford Council's Green group, had mixed feelings about promoting Sunday trading.

He warned: "We appreciate we have to keep up with other shopping areas, but we also appreciate there are staff issues where people feel compelled to work on Sundays and the effect this can have on families.

"Flexibility of opening during the week would be better - Sunday opening has not been good for this country on the whole."

His concerns were echoed by independent trader Table Decor, on Darley Street.

Chris Bexon, owner of the shop said: "We only open five days a week because we believe our staff need two full days off from work.

"We don't open on Sundays, except in the run up to Christmas, because it just isn't worth it. People don't want to come to a city centre store on Sundays, they want to travel to shopping malls."

The completion of the £300 million Broadway shopping scheme could see the city move much closer to becoming a seven-day city.

Opening hours of the centre, which is expected to be finished in 2008, have not yet been announced. But John Burton, UK development director for developers Westfield, has said it will not be sticking to traditional times and shutting at 5pm.