Dr Mahathir Mohamad said that Prime Minister Najib Abdul Razak still has a lot of work to do before calling the recent negotiations with Singapore a success.

"I at first hoped that all outstanding matters will be settled, but it would seem that a lot of issues have been left untouched," he said.

He pointed to the still unresolved issue of the price of water to be supplied to the island nation after 2011, the Central Provident Fund contributions for Malaysians working in Singapore and the third bridge as some of the issues which the negotiations have left unaddressed.