Chinese authorities are understood to be extending the ban on new Hollywood films being released over the Christmas period until the end of the Chinese New Year holidays, according to local sources.

China's year-end box office season, which is traditionally reserved for local movies, officially gets underway tonight with the grand premiere ceremony of Peter Ho-sun Chan's The Warlords in the Beijing Olympics Sports Centre.

However this year, according to cinema owners in Beijing and Shanghai, the season will be prolonged to the end of the Chinese New Year holidays, around mid-February. During this season, eight local blockbusters will open while no revenue-sharing foreign films will be scheduled for release.

A Beijing-based cinema owner confirmed that Wong Kar-wai's My Blueberry Nights is the only foreign film scheduled for release during this period, and is set to open on Dec 22. However, the film is classified as domestic by Chinese authorities as it's a co-production between Shanghai Film Group, Wong's Hong Kong-based Jet Tone Productions and France 's StudioCanal.

Another local industry player, who declined to be named, revealed that the black-out might be prolonged to the beginning of April: 'Basically, during the season, the market will see mainly non-American films.'

Traditionally, December and Chinese New Year (usually from end of Jan to mid-Feb) are reserved as two major periods for Chinese filmmakers to promote their films. During the month of December and two weeks in February, no new foreign blockbusters can be released. This year, foreign films are likely to be blocked for six more weeks from January to mid-February.

It is estimated that two to four US studio movies will be affected by the prolonged black-out. Two Hollywood blockbusters - The Guardian and Casino Royale - were released in January of this year.

It is yet to be confirmed whether the prolonged black-out will become policy. China Film Group's spokesperson declined to comment and the Film Bureau under the State Administration of Film, Radio and Television (SARFT) could not be reached as of press time.

However, the move is generally seen as China 's attempt to curb the fast increasing box office of foreign films and to promote local productions. By the end of June this year, foreign films had a market share of around 60%. In the past three years, Chinese films have generally maintained a more than 50% market share.

Efforts have been made to cool down foreign film sales, beginning from July, when Transformers swept the Chinese box office, reaching $35m (RMB280m).

Shortly afterwards, Harry Potter And The Order Of Phoenix had its number of release prints cut down. Last month, Die Hard 4.0 and Bourne Ultimatum were scheduled to open head-to-head and had their print count reduced to around 150 prints each, allegedly because Ang Lee's Chinese-language film Lust, Caution was still dominating screens. Lust, Caution has so far raked in $16.24m (RMB120m)

It has also been rumoured in the local industry that foreign film releases will be restricted to 200 prints each next year.