Singapore and Malaysia's state-owned investment companies have agreed to develop jointly projects in the two countries.
Temasek Holdings and Khazanah Nasional will develop $9.8bn (£6bn) worth of projects in Southern Malaysia and central Singapore.
The announcement comes as the two countries signed a deal resolving a long running land dispute.
The developments will include commercial and residential components.
"Both these projects mark our first joint development investment with Temasek, and we look forward to a strong and fruitful partnership in both Singapore and Iskandar Malaysia," said Azman Hj Mokhtar, Managing Director of Khazanah.