A New York Times reporter left Beijing Thursday after authorities did not grant him a visa, sparking ire in Washington as China ratchets up pressure on foreign media.

The United States said it was "deeply concerned that foreign journalists in China continue to face restrictions" after the reporter, Austin Ramzy -- who had been based in China for more than six years -- headed to Taipei.

"China is forcing out Austin Ramzy today after 6.5 years," Times China correspondent Ed Wong wrote on Twitter.

"And we're off. Next stop, Taipei," Ramzy tweeted. In an earlier message, he wrote: "Sad to be leaving Beijing. Hope I can return soon."

Ramzy's departure comes a month after US Vice President Joe Biden raised the issue of China's treatment of foreign journalists privately with Chinese leaders during a visit to Beijing.

Beijing has blocked the websites of both the Times and Bloomberg News after they published investigations in 2012 into the family wealth of former premier Wen Jiabao and President Xi Jinping, respectively.

Authorities also reportedly conducted unannounced "inspections" of Bloomberg's offices in Beijing and Shanghai last month and demanded an apology from its editor-in-chief amid a controversy over an unpublished article on the government ties of a Chinese billionaire.

China's foreign ministry this week said that Ramzy's journalist visa, which the newspaper applied for in June after he joined from Time magazine, would not be ready before the end of the month, effectively obliging him to leave.

The Foreign Correspondents' Club of China (FCCC) said it "strongly regrets" that Ramzy "has been forced to leave" and criticised China's behaviour, saying it "falls well short of international standards".

He is the third New York Times journalist to not be authorised to stay in China in 18 months, it pointed out in a statement.

"In these circumstances it is difficult to avoid the conclusion that the authorities are punishing the New York Times for articles it published concerning Premier Wen Jiabao and his family."

Chris Buckley, a veteran Reuters China correspondent hired by the Times, similarly had to leave Beijing when his previous visa expired in December 2012.

Philip Pan, the Times's designated Beijing bureau chief, has been waiting for nearly two years for Chinese authorities to grant him a visa and covers the country from Hong Kong.

Asked about China's treatment of foreign journalists, foreign ministry spokeswoman Hua Chunying denied any expulsions.

"There's no such thing as foreign journalists being expelled from China," Hua said Wednesday at a regular news briefing, adding: "It is Chinese domestic affairs.

"We are firmly opposed to any individual or any government or organisation interfering in China's domestic affairs."

Chinese authorities have also said that Ramzy breached visa rules by not changing his status after leaving Time, but the FCCC disputed the accusation.

On Thursday, a White House statement said the US was "very disappointed" that Ramzy was obliged to leave China and that Beijing's actions "stand in stark contrast with US treatment of Chinese and other foreign journalists".

"The United States is deeply concerned that foreign journalists in China continue to face restrictions that impede their ability to do their jobs, including extended delays in processing journalist visas, restrictions on travel to certain locations deemed 'sensitive' by Chinese authorities and, in some cases, violence at the hands of local authorities," it said.

"We urge China to commit to timely visa and credentialing decisions for foreign journalists, unblock US media websites and eliminate other restrictions that impede the ability of journalists to practice their profession."

Last week, foreign journalists covering the trial of activist Xu Zhiyong in Beijing were harassed and manhandled by uniformed and plainclothes police.