A request by Macau for more space on the neighbouring mainland island of Hengqin has brought a call for Hong Kong to follow suit and seek to expand into Shenzhen or Guangzhou.
Macau Chief Executive Dr Fernando Chui Sai-on said five square kilometres allocated on the island for joint cross-border development was not enough and "we have decided to officially request more land on Hengqin from the central government".
Dr Bill Chou Kwok-ping, an associate professor of political science at the University of Macau, said that was sensible given the size of Macau - 31 square kilometres - and its population of about 610,000.
Announcing the Hengqin New Area, as the district is known, in 2009, then vice-president Xi Jinping hailed it as a "demonstration area" for co-operation between Guangdong, Hong Kong and Macau. In the same year, Macau paid about HK$1.2 billion to rent a square kilometre for 50 years for an extension of the University of Macau that opened last year.
City University political scientist Dr James Sung Lap-kung said Hong Kong could consider a similar mode of development. "Renting land in neighbouring mainland cities will be a good option," he said. "Like it or not, there is a need for deeper integration between Hong Kong and Guangdong if Hong Kong is to further develop."
While Hong Kong is also co-operating with Shenzhen to develop its Qianhai district, Sung said the pace of that development was too slow.
Dr Chung Kim-wah of Polytechnic University said the Hengqin model could be "too politically sensitive" for Hong Kong.