KUALA LUMPUR (REUTERS) - Iskandar Waterfront Holdings, a Malaysian property developer focused on the southern state of Johor, has postponed an up to US$300 million (S$373 million) IPO to the last quarter of 2014 due to property cooling measures, two sources said on Monday.

The firm, tasked with developing a metropolis in Johor state that neighbours Singapore, had previously deferred the listing to early 2014 from an initial target to sell shares in this current quarter.

The IPO is a casualty of the Malaysian government's plan to raise real property gains taxes next year and double the minimum price at which foreigners can buy property as it seeks to cool prices.

"The assets have to be revalued now with the changes in real property gains tax," said one of the sources. The sources declined to be identified as the matter was private.

Officials in Iskandar could not be immediately reached for comment.