Prime Minister Lee Hsien Loong will travel to Putrajaya to meet his Malaysian counterpart, Tun Dr Mahathir Mohamad, for a leaders' retreat next month.

It will take place about 10 days after Dr Mahathir comes to Singapore for the Asean Summit, PM Lee said at a recent dialogue with Singaporeans.

Singapore, as the Asean chair this year, is hosting the summit that will take place from Nov 11 to 15.

The retreat with Dr Mahathir is an annual meeting between the leaders of Singapore and Malaysia.

PM Lee said Singapore's relations with Malaysia are stable.

"The High-Speed Rail (HSR) was an issue potentially, but we worked out a two-year deferment for the HSR project and that was a constructive resolution of what could have been a spiky dispute," he said.

He added: "I hope that at the retreat, we will be able to look ahead, to discuss win-win opportunities in order to deepen our cooperation and friendship."

Earlier this month, PM Lee was in Bali for another annual retreat. That was with Indonesian President Joko Widodo, popularly known as Jokowi.

Ties with Indonesia are good, the Prime Minister said. "Economic cooperation is progressing, and President Jokowi hopes to attract more Singapore investments."

PM Lee noted that Indonesia is going to hold national elections in April next year.

"We hope to keep relations stable during their campaign and to pick up our cooperation with them afterwards."