LONDON, Jan 28 (Reuters) - Algeria's In Amenas gas plant, which was attacked by Islamist militants a year ago, will be operating at full capacity within weeks as work on the last of its three processing units is nearing completion, a senior Algerian energy official said.
In Amenas produced about 11.5 percent of Algeria's natural gas output before the attack and full resumption would free up more of the fuel for export to Europe.
"Two thirds of capacity is already on stream and the last unit will start in a few weeks so In Amenas will be back at full capacity in a few weeks," Ali Hached, senior adviser to Algeria's energy minister, said on the sidelines of a conference in London on Tuesday.
He said the capacity of the site was about 30 million cubic metres per day and that it was currently producing around 20 million cubic metres.
Norway's Statoil, which operates In Amenas with BP and Algeria's state-owned Sonatrach, said in May that production at the second of the three processing trains had resumed but that it was unclear when then third would reopen.
Forty oil workers, all but one foreign, died at In Amenas in January after the militants took expatriates hostage during a four-day siege that ended when Algerian forces stormed the site.
BP Chief Executive Bob Dudley told a conference call for analysts in October that expansion projects for In Amenas and In Salah gas producing sites would not get going in 2014 as planned.
BP has yet to send foreign contractors back to In Amenas though Algerian officials said new security reinforcements and a landing pad were in place at the desert complex.
BP has said it expects to return personnel to the Algerian sites once agreed security measures are in place.
Statoil said in November some of its staff had returned on a permanent basis to its operational centre at Hassi Messaoud, some 700 km (435 miles) to the southeast of Algiers but that it would take more time to return to In Amenas.
Hached said the companies were gradually returning their staff to sites deep in the desert, starting with oil and gas producing complex Hassi Messaoud, and would eventually go back to sites at In Salah and In Amenas.