It is scheduled to open by the end of the year.

With people working longer hours, the developer hopes to capture night-owl shoppers with its latest concept, while allowing APM tenants to maximise their business opportunities.

Extending opening hours seems a sensible move, as retail rents in Hong Kong are relatively expensive compared with the region. For instance, property consultants Cushman & Wakefield Healy & Baker ranked Causeway Bay, at an annual average of US$500 per square foot, as the world's third-most expensive shopping district last year.

Most shopping centres in Hong Kong close by 10pm, with some restaurants staying open until 11pm.

SHKP - Hong Kong's largest private shopping-centre owner - has taken this one step further.

The developer has stipulated that all retail shops at the 11-storey APM Mall - part of the Millennium City 5 project - stay open until midnight. Restaurants will close at 2am, and the entertainment zone - comprising karaoke bars, Japanese game centres and possibly a cinema - will operate 24 hours a day.

More than 50 per cent of the centre's 630,000 square feet has been designated for restaurants and entertainment.

Maureen Fung, deputy leasing manager of SHKP subsidiary Sun Hung Kai Real Estate Agency, said there were few shopping and entertainment choices for those working until 10pm or later.

'We came up with this concept after seeing the hectic lifestyle of Hong Kong people,' she said.

But other shopping centre operators such as Wharf (Holdings) and the Mass Transit Railway Corporation - which operates four shopping centres along its rail lines - expressed no interest in the idea, saying the hours did not make it viable.

Doreen Lee Yuk-fong, a director of Wharf which owns Harbour City in Tsim Sha Tsui and Times Square in Causeway Bay, said the existing operating hours, with shops closing at 10pm and restaurants at midnight, were fine.

'In general, we see fewer visitors after 9pm,' she said.

Although a small number of tourists did last-minute shopping, it was not enough to convince shops to stay open for longer.

'Business volume is the determining factor,' she said.

Hiring staff for extra shifts and higher electricity consumption would also drive up retailers' costs, she said.

Ms Lee said the company had difficulty five years ago convincing tenants to extend their opening hours at Harbour City. At the time, most shops closed at 7pm to 8pm.

'We offered all sorts of incentives such as free air-conditioning to encourage them to open longer,' she said.

Chan Ka-ming, chief shopping centre manager at the MTRC, said it saw no need to extend opening hours at its shopping centres.

However, with APM Mall only two stops away from Telford Plaza at Kowloon Bay MTR station, some shoppers might be lured away.

'Families and office workers are our target and they will not shop after midnight,' Mr Chan said.

Telford Plaza closes at 10pm, with a few restaurants staying open until 2am, he said.

To encourage longer opening hours, SHKP said APM tenants would enjoy management fees of $8.5 per square foot, about 15 per cent below the market level.

Ms Fung said rental charges would be $80 to $200 per square foot, against $100 to $200 per square foot in smaller shopping centres in the area.

She said the APM Mall aimed to attract teens and twentysomethings looking for new trends.

'Most stores will operate under a new concept where retailers integrate fashion and coffee or games. Some new sushi restaurants from Japan will open their first stores [at APM],' she said.

To keep shoppers inside as long as possible, Ms Fung said 100 plasma displays would be strategically placed to keep them in touch with the outside world.

'So customers will not need to rush home to watch their favourite programmes or miss anything while shopping,' she said.