A few kilometres off the Chinese coast, Beijing has appointed a Taiwanese citizen as deputy chief of an experimental "common homeland" that is an unusually forward overture to Taipei.

Pingtan island is physically China's closest spot to Taiwan, and is now also being transformed into its nearest approximation of a unified country, as part of Beijing's long-held dream to reclaim the self-governing neighbour it considers a rogue province.

New towers crowd the shoreline and the glow of construction sites fills the night, while Taiwanese are being invited to serve in government, drive Taiwanese-licensed cars and open Taiwanese currency bank accounts.

But the economic potential of the "experimental zone" has yet to be proved, and with Beijing setting the rules, its hints at political integration may well be rebuffed.

"It's basically the Chinese creating what they see as what future integration would look like -- without really much input from Taiwan," said Bonnie Glaser, a senior adviser at the US-based Centre for Strategic and International Studies.

"It may help some individual Taiwan companies make some money, but I don't think it's going to promote the political goals that they seek," she added.

"The political symbolism in all of this is seen as potentially threatening to Taiwan."

China's brutal civil war ended in 1949 with the Communist Party controlling the mainland and the defeated Nationalists retreating to Taiwan.

For decades the threat of conflict loomed, with both sides claiming to represent the whole of China.

Beijing has described reunification as a "historical mission", to be imposed by force if necessary.

But at the same time a "one country, two systems" model is on offer, similar to the arrangements with Hong Kong, the former British colony turned semiautonomous Chinese territory.

Beijing has sought warmer ties in recent years and in February a minister from Taipei will visit the mainland in the two sides' first official contact in six decades.

'Joint' project

Meanwhile authorities have also sought to attract Taiwanese -- along with their investment and knowhow -- with generous subsidies and fast-track business services.

Pingtan goes further, with Beijing promising it will be "jointly planned, jointly developed, jointly operated, jointly managed, and jointly profiting".

The project has been allocated at least 250 billion yuan ($41 billion) since it was approved in 2009 -- when it was an outcrop of humble fisheries that did not even have a bridge connecting it to the mainland.

Now shiny brochures promise an island bursting with gleaming skyscrapers, leafy villas and Asia's largest private museum.

Taipei's Mainland Affairs Council in 2012 distanced itself from the project and its claim to be a "joint" effort.

But Beijing is pressing ahead, recruiting Taiwanese to fill deputy posts across the local government, in what University of Nottingham lecturer Chun-Yi Lee called both a symbolic step and an effort to absorb outside experience.

A 50-year-old finance expert, named Liang Qinlong according to mainland Chinese transliteration, has been appointed deputy chief of the zone's management committee, an official told AFP.

Liang could not give interviews due to sensitivities with Taipei, he added.

Pingtan's economy grew 16 percent in the first half of 2013, and as of November 129 Taiwan-funded businesses had set up shop, the China Daily reported.

"The State Council has an overall policy of offering lots of benefits to Taiwanese and we are very happy to see those being gradually put into place," said Shuie Chin Te, a 50-year-old Taiwanese businessman who recently recruited his son-in-law to join him on the island.

Still, Pingtan must prove it can become more than an overgrown construction site.

A new port has been built to receive ferries from Taiwan, but daily services have yet to begin.

A Taiwanese restaurateur surnamed Chang, sitting in an empty food court, said he was losing patience after nearly three years of bad business.

"Beijing is really promoting this, they want to make it even better than Hong Kong or Shanghai, so the opportunities are limitless -- but the policies are coming too slowly," he said.

Meanwhile the onslaught of development has made winners and losers of the original islanders.

Some complained that construction work went to non-local crews brought in by developers while living costs had spiked, and a fisherman surnamed Chen said their seaside houses were being torn down.

"There have been no benefits at all," he said.

But 28-year-old art entrepreneur Lin Ping said business prospects had soared and the new bridge and roads had slashed travel times.

"If it weren't for Taiwan, Pingtan wouldn't be all that it is today," he said. "As for promoting reunification, that's hard to say."