Hong Kong’s police chief said on Tuesday he suspected Causeway Bay bookseller Lee Po was hiding something, but that the force would have to accept his story that he had sneaked

into the mainland of his own free will in order to help with an investigation.

Commissioner Stephen Lo Wai-chung said there was no point in seeking another meeting with Lee in the near future, after he met a police officer and an immigration officer on Monday, six weeks after Hong Kong made the request.

Lo also said there was no evidence to support speculation that Lee was kidnapped by mainland agents last December over the sale of banned books across the border.

The force is in a dilemma as to how to proceed with its investigation into Lee’s mysterious disappearance, as he has made clear to the visiting officers that he does not want their help.

The controversy took yet another diplomatic twist on Tuesday, with a British government spokesman telling the Post the UK was still “ready to provide consular assistance” to Lee and his wife, even though they had both decided to give up their British citizenship.

The Swedish foreign ministry also told the Post that its staff from the Beijing embassy on February 24 had been allowed to visit Gui Minhai, a colleague of Lee’s and a Swedish national, who also went missing and turned up on the mainland. A ministry spokesman would only say Gui was “well”.

Grilled by reporters about Lee on Tuesday, Hong Kong’s police chief said: “We don’t see [evidence] that he was forcibly taken away. We have met Mr Lee in person, and he said that he used his own means to leave Hong Kong for the mainland. Thus, at this moment when we do not have other evidence, we have accepted what he said.”

However, Lo admitted that Lee was not telling them the full story.

“I believe that if we are to meet him again in the near future, there will be no new updates. There was something he did not reveal to us,” Lo said.

Before Lee vanished at the end of December, Gui disappeared from Pattaya in Thailand in October. Their publishing colleagues, Lui Por, Lam Wing-kee and Cheung Chi-ping, disappeared that same month, but everyone surfaced across the border later.

Lee stuck to his story on Monday that he was not kidnapped and was helping with an investigation into Gui, who has been accused of smuggling banned books into the mainland. He asked Hong Kong police to drop their investigation. But the police chief said the investigation was not yet over.

“We will wait for him to come back to Hong Kong. Once he is here in Hong Kong, when we have the right to carry out law enforcement duties, we will meet him again,” Lo said.

Meanwhile, some Hong Kong delegates to China’s parliament and top political advisory body intend to press the central government for answers at annual meetings of the National People’s Congress and the Chinese People’s Political Consultative Conference in Beijing this month.

Michael Tien Puk-sun, a local delegate to the NPC, said: “Lee Po still has not explained how he ended up on the mainland. I am concerned if the mainland authorities had exercised duties across the border.”

Another NPC delegate, Miriam Lau Kin-yee of the Liberal Party, will ask Beijing to reveal more details “at a suitable time”.