China on Friday threatened "counter-measures" against Sweden if the culture minister awards a Swedish rights prize as planned to detained Chinese-Swedish book publisher Gui Minhai.

A Chinese-born Swedish citizen known for publishing gossipy titles about Chinese political leaders out of a Hong Kong book shop, Gui Minhai, 55, disappeared while vacationing in Thailand in 2015 before resurfacing in mainland China several months later.

"China resolutely opposes Swedish PEN awarding a criminal and lie-fabricator... We oppose even more resolutely any Swedish government officials attending the award ceremony," China's ambassador to Sweden Gui Congyou said in remarks published in English on the embassy website.

"We will surely take counter-measures," he said. "Some people in Sweden shouldn't expect to feel at ease after hurting the feelings of the Chinese people and the interests of the Chinese side.

"Normal exchanges and cooperation will be seriously hindered," he said.

He told Swedish news agency TT that any government representative attending the ceremony would be declared unwelcome in China.

Swedish Prime Minister Stefan Lofven said the Scandinavian country would not back down.

"We are not going to give in to this type of threat. Never. We have freedom of expression in Sweden and that's how it is, period," Lofven told Swedish Television.

Culture and Democracy Minister Amanda Lind was due to present Swedish PEN's Tucholsky Prize to Gui Minhai at a ceremony on Friday evening in Stockholm.

Currently in detention at an unknown location in China, he will be represented by an empty chair on the stage. Lind termed Beijing's threat as "serious".

Copyright Agence France-Presse, 2019