The telecommunications company, with 32 per cent of the Republic's mobile subscribers, can grab another 10 per cent to 15 per cent of the market, said Cazenove's telecommunications and media analyst, Mr Lai Voon San.

StarHub offers bundling discounts to those using all three of its services, so the new rules should help it entice consumers into signing up for its mobile plans, said Mr Lai.

StarHub customers who sign up for the firm's pay-TV service, broadband and mobile post-paid plans get discounts on all three.

The new phone number portability rules are expected to kick in by the third quarter of the year.

Given StarHub's pay-TV dominance, there is 'little other operators can do', said Mr Lai, although he acknowledged that the other operators, in particular SingTel, which has deep pockets, could launch aggressive promotional campaigns to fight back.

Mr Lai said besides losing mobile subscribers to StarHub, SingTel's prospects in Australia are also 'unlikely to see a turnaround this year'.

The key driving force behind SingTel, which Mr Lai described as 'somewhat of a safe haven', is its portfolio of regional associates such as India's Bharti and Indonesia's Telkomsel.

Based on SingTel's closing price of $3.86 yesterday, this is already 'well-priced into the stock', he said.

While SingTel has 'done an extraordinary job monetising its value', it is possible for an investor to buy directly into the associates, which are themselves listed companies, and cherry-pick the best Singapore telco.

This clearly requires more work on the part of the investor, Mr Lai acknowledged, but the returns should be worth it.

He does not believe SingTel's mio TV pay-TV service will be successful in the next few years or will help it fend off StarHub, as long as StarHub maintains its death-grip on content such as the English Premier League.

As for MobileOne (M1), it remains attractive for its good dividend yield of 9.7 per cent - the highest for all Singapore's three listed telcos.

This generous dividend yield alone makes M1, which closed yesterday at $1.90, the cheapest telco stock in the region, said Mr Lai.

While it has no other services besides mobile to offer customers, he said, M1 will be able to keep 90 per cent to 95 per cent of its income and should thus 'remain buoyant'.