Hong Kong's public radio station has replaced its 24-hour BBC World Service broadcast with Chinese state-run programming, in a move the British broadcaster called "disappointing" as concerns grow over Beijing's influence on the semi-autonomous city.

Listeners woke up on Monday morning to the Mandarin-language broadcast of the China National Radio Hong Kong Edition (CNR), instead of the World Service, which had been relayed live by Radio Television Hong Kong (RTHK) since 1978.

The BBC said it was "always disappointed when a service our listeners are used to changes" with listeners launching a petition to bring back the World Service.

RTHK has a number of different channels offering some programmes in English. The World Service was broadcast on Channel 6, which is now playing CNR.

The CNR broadcast includes news, culture and lifestyle programming mostly in Mandarin -- the language most commonly spoken in mainland China.

Only some of its content is in Cantonese, which is the dominant language of Hong Kong, leading to criticism that this was another step towards the "mainlandisation" of Hong Kong.

RTHK is still running a reduced version of the World Service on a different channel, but only late at night, from 11pm to 7am.

China stands accused of tightening its grip on Hong Kong, with critics also blaming the pro-Beijing local government for acting as a puppet.

The jailing of prominent young pro-democracy activists last month and the unveiling of a controversial rail link to the mainland that would see a portion of the city come under Chinese law have worsened fears the city's cherished freedoms are being eroded.

An online petition against the change to the World Service programming had received over 1,000 signatures by Tuesday morning.

"The removal of the BBC World Service from the airwaves makes the city feel more parochial and inward-looking," the petition said.

Longtime resident Alex Hofford, who organised the petition, said he had nothing against the CNR broadcast but does not believe it should have come at the expense of the BBC.

"This is a sad day for Hong Kong, I'll really miss the Beeb as I drive around Hong Kong during the day," Hofford said.

RTHK's head of corporate communications Amen Ng told AFP Tuesday that it was a "difficult decision" due to "limited radio frequency".

She described the CNR broadcast as "tailor-made" for Hong Kong.

"This is a cultural exchange between mainland China and Hong Kong," Ng added.

Hong Kong was handed back to China by colonial ruler Britain in 1997 under a "one country, two systems" agreement designed to protect its freedoms and way of life, but there are growing concerns those rights are now under threat.