SINGAPORE - Prime Minister Lee Hsien Loong congratulated newly-minted Malaysia PM Mahathir Mohamad on his appointment in a phone call on Friday morning (May 11).

PM Lee said in a Facebook post on Friday afternoon that he wished Dr Mahathir and his government all the best.

He added that he hopes to be able to catch up with Dr Mahathir in person either in Kuala Lumpur or Singapore very soon.

"He was busy meeting people for his Cabinet appointments!" PM Lee noted in his post, where he also shared a photo of the both of them taken nearly 20 years ago.

The photo shows Dr Mahathir and PM Lee at the Hari Raya Open House in Johor Baru in December 2001.

Dr Mahathir was sworn in as Malaysia's seventh Prime Minister on Thursday night, a day after his Pakatan Harapan coalition delivered a shock win at the Malaysia election, which ended the six-decade rule by the Barisan Nasional.

In a statement on Friday, the Singapore Ministry of Foreign Affairs said PM Lee is looking forward to working with Dr Mahathir to further strengthen and deepen bilateral cooperation for the mutual benefit of both countries.