BP announced tonight that it would sell its Sunray and Hemphill plants to Eagle Rock Energy Partners. The deal does not include BP’s natural gas producing assets in the area and is expected to close in the fourth quarter.

The move comes as the oil price ended five days of gains today after gloomy growth data from China pushed down forecasts of oil demand growth for next year.

Brent crude traded 27 cents lower at $112.95 in London, its first daily fall since August 2.

The International Energy Agency (IEA) said that “sluggish economic growth” could restrict annual oil demand growth to 800,000 barrels of oil per day (bpd) next year, down from its prediction last month of 1m bpd.

“Marginally weaker economic drivers leave the 2013 demand growth outlook 150,000bpd lower than previously assumed,” the IEA said. “Global economic growth of around 3.3pc is anticipated in 2012, rising to 3.6pc in 2013 – down marginally from last month’s 3.8pc as the economic backdrop has worsened,” it added

The biggest reduction to forecasts was in China, with 2013 GDP growth forecast revised down to 8.1pc in 2013, from 8.5pc previously.

The IEA report was released just as Chinese export data for July came in well below forecasts.

Exports rose just 1pc year on year, compared with a forecast 8.6pc growth, and down from 11,3pc growth in June. Shipments to the EU fell more than 16pc, stoking fears of faltering demand from China’s biggest foreign customers.

The IEA also cut its economic growth outlook for the US for 2013, to 2pc, from 2.3pc forecast last month.

The report said that oil production from Iran had fallen to 2.9mbpd, below that of Iraq, at 3.02mbpd, for the first time since the late 1980s.

As sanctions on Iran tighten it will “likely continue to face major difficulties in placing its exports”, the IEA said.