LONDON - BP is still considering the construction of refineries in China with partners Sinopec and PetroChina, the head of the British oil major's downstream unit said on Tuesday.

Iain Conn, head of oil refining and fuel marketing, said BP was in exploratory talks and that any decision to proceed hinged on whether China decided it needed new refineries.

We have been discussing Chinese refining sites with Sinopec for some time. We would, under the right circumstances, wish to enter a joint venture with Sinopec in China, he told reporters at the sideline of a press conference to announce BP's second-quarter results.

BP has long been interested in building a refinery next door to the Shanghai petrochemical complex it operates with Sinopec, and the London-based company is also evaluating other sites.

The timing of that depends on the evolution of the market. This is not subject to negotiation, he added.

Conn added that BP, which has sold several refineries in recent years, was not seeking to sell any plants at this time.

He said the company was not marketing its stake in a New Zealand refinery, operated by New Zealand Refining, and nor was it interested in buying out its partners, Royal Dutch Shell Plc and Exxon Mobil, which he said were trying to sell their stakes. (Reporting by Tom Bergin, editing by Will Waterman)