Fortis Healthcare led by Malvinder Mohan Singh has launched a $3.1 billion (S$4.3 billion) counter bid for Singapore's Parkway Holdings, trumping a rival offer by Malaysian state fund Khazanah.

Fortis, which holds around 25 per cent stake in Parkway Holdings, has offered to buy all of Parkway for S$3.8 a share, against Khazanah's offer of S$3.78 a share, the electronic media reported today.

The offer is at a slight premium to Parkway's last traded price of S$3.57. Trading in Parkway shares in the Singapore Stock Exchange has been halted. The last traded price stood at S$3.80 per share.

Khazanah, the second-largest shareholder in Parkway, had, earlier, made a surprise $835 million partial offer in May to lift its stake to 51.5 per cent before Fortis could build a controlling stake in the Singapore firm.

Fortis' chairman Malvinder Mohan Singh, who shifted residence to Singapore, is also the chairman of Parkway Holdings.

Fortis has made the offer to acquire the stake in Parkway through Singapore-based RHC Healthcare Pte, which has also offered to acquire all the shares of Parkway.

The offer, however, is conditional on Fortis getting at least 50 per cent stake in the Singapore firm.

Macquarie and Royal Bank of Scotland are the financial advisors to the offer.

RHC is indirectly controlled by Fortis Healthcare promoters Malvinder Mohan Singh and Shivinder Mohan Singh.

Both Fortis and Khazanah sees Parkway as a base for expanding operations Asia-wide as the hospital chain has centres in Singapore, Malaysia, India and China.

Parkway, Asia's largest listed hospital group, runs 16 Hospitals across Asia.