He met Fu Ziying, director of Beijing’s liaison office in the casino hub.

Pineapple politics: Beijing-friendly Taiwanese mayor omes bearing fruit

“The noise and scepticism are simply boring and pointless ... Kaohsiung must open its mind and embrace people from all walks, including every business opportunity ... So we welcome all visits and there is no dark side to this,” Han said.

Also on Saturday, Taiwan’s president Tsai Ing-wen, who is visiting the West Pacific island country of Palau, said China might be using Han’s visit to set the stage for introducing the “one country, two systems” policy in Taiwan, according to the Central News Agency.

“The liaison office is an important department for China to implement one country, two systems in Hong Kong,” Tsai said. “It’s difficult to rule out the possibility that [China was trying to] create an atmosphere for the policy by arranging for Han to visit the office.

“I don’t know if he is aware of that,” Tsai added.

Han is the first Taiwanese mayor to meet Beijing’s top man in the city and the first mayor to meet Hong Kong’s leader since 2014.

The dinner event on Friday, hosted by the liaison office, was part of Han’s high-profile visit to Hong Kong and three other Chinese cities – Macau, Shenzhen and Xiamen – to promote trade.

Four pro-Beijing groups in Hong Kong and six mainland companies had earlier agreed to import a total of HK$690 million (US$87.9 million) worth of fruit, fish and other agricultural products from Kaohsiung in the next one to four years.

Kaohsiung also signed 27 agreements with a total of 49 Macau companies and bodies involving HK$180 million.

Han’s trip coincided with wide speculation that the KMT would summon him to join the primary for Taiwan’s presidential race in 2020.

On Friday afternoon, Sino Land tycoon Robert Ng Chee Siong had hosted a separate reception for Han, fuelling belief the latter was on his path to presidency. “You all have to encourage him to step up. Please encourage him!” Ng said. He also expressed Sino’s willingness to invest in Kaohsiung.

Han on Saturday reiterated that for the time being, he was focused on promoting trade and making friends across the straits.

But liberal politicians from Hong Kong and Taiwan said the liaison office dinner, which was not officially announced, went beyond just trade.

Taiwanese lawmakers Su Chiao-hui and Hsu Chih-chieh of the Democratic Progressive Party (DPP), as well as pro-independence New Power Party said Han had undermined the sovereignty of the self-ruled island. They called for a detailed account of his exchange with Wang.

Chiu Chui-cheng, deputy minister of Taiwan’s Mainland Affairs Council pointed out that Han’s meeting with the liaison office was not previously publicised, urging the mayor to clarify the situation and allay doubts.

DPP secretary general Luo Wen-jia also criticised Han for knowingly meeting the liaison office, even though it had been accused of “effectively giving orders in Hong Kong” and undermining the city’s freedom.

“Today there are talks within KMT to summon Han [to join the primary]. Outside, the Communist Party’s liaison office is ‘summoning’ Han – the two parties are now joining hands,” Luo said in a Facebook post. “No wonder Hong Kong critics said [his trade deals] are deals with the devil.”

Han had previously dodged a question on his take on Xi’s proposal.

Han Kuo-yu, Carrie Lam and Wang Zhimin. What does it mean for cross-strait ties?

Meanwhile, Hong Kong’s pro-democracy lawmakers Eddie Chu Hoi-dick, Au Nok-hin, Leung Yiu-chung, and activist group Demosisto called Han’s meeting with Wang “inappropriate”.

“Trade between Kaohsiung and Hong Kong certainly falls within the remit of the Hong Kong government, and that has nothing to do with the liaison office,” they said in a statement.

“Out of respect for Hong Kong’s one country, systems, it is unheard of for official guests to meet ... the director of the liaison office.”

Ousted lawmaker Nathan Law Kwun-chung said the meeting conveyed Beijing’s “blessing” for Han instead of being about trade promotion.

Speaking before departing Hong Kong to meet Macau Chief Executive Fernando Chui Sai-on, Han said he had a warm and great dinner with Wang, and mainly discussed increased exchange between the two cities.

“We talked about everything – past engagements, the bitterness and sweetness of life, our wives and children, as well as the future of Hong Kong and Kaohsiung.”

He was quick to clarify that he did not broach the sensitive issue of “Taiwan’s future” to Wang. Asked to respond to criticisms by Hong Kong politicians, he appeared reluctant.

“As the mayor of Kaohsiung, I should not comment too much on Hong Kong’s internal matters ... Also we should be clear what we are here for.”

The DPP – to which Taiwan president Tsai belongs – and the KMT have previously pushed back against Chinese president Xi Jinping’s proposal to adopt the one country, two systems model and start talks of unification.

Han, known for his colourful and populist speeches, was earlier criticised on his Hong Kong trip for mocking Bhutan’s people as “silly” in a casual remark while comparing the Taiwanese and Bhutanese.

In Macau, he also incorrectly said there was no direct flight between Macau and Kaohsiung, something he looked forward to discussing with Fernando Chui, when in fact, there are 32 flights between the two cities weekly.

“I only slept four to five hours a day and so I wasn’t speaking clearly – do forgive me,” he said of the faux pas and factual error.

Additional reporting by Su Xinqi