This somewhat 'futuristic' scenario moved a step closer to reality on Wednesday, with the launch of one of the largest public trials of such mobile payment technology here.

Run by StarHub and EZ-Link, the trial will have 1,000 users use their phones like electronic wallets. They simply tap their phones when paying for bus and train rides, as well as items at McDonald's and 7-11 convenience stores.

Altogether, there will be about 20,000 ez-link machines that can read these specially-made phones, which are loaned to the trial users for six months.

To top up their phones, users can tap them at an EZ-Link top-up machine at an MRT station, for example.

This trial, first announced last month, comes as the push for mobile payment gathers momentum.

Despite failing to gain widespread use in several tests in 2001, companies are still keen to get users paying with their phones, in the hope that they will spend more.

In a separate trial that started last month, SingTel and Nets are letting users pay with their phones at 1,000 outlets like Cheers convenience stores. A commercial service may be out by next year.

Mr Nicholas Lee, EZ-Link's senior vice-president of business and technology, said his company has not decided when to roll out a commercial service.

But it was a matter of when, and not if, such technologies are here, he told reporters on Wednesday.

Mobile payment has taken off in Japan, where millions of people pay for anything from instant noodles to train rides with their do-it-all wallet phones.

Industry experts say this can work here too, because the wireless technology used here - called near-field communications or NFC - will mature in the next few years.

Said Mr Jeroen Keunen, a senior director at NXP Semiconductors, which makes the chips used in new NFC phones: 'Like with Bluetooth, you will see more competition, which will drive costs down and bring mass adoption.'