* US, Canadian, German ventures restarting in east
* Largest Ras Lanuf refinery could resume processing in days
* Many still reluctant to return due to security concerns
By Jessica Donati
JAKHIRA, Libya Foreign companies are quietly returning to Libya's oil fields east of Sirte, deploying skeleton teams to an area of the hydrocarbon-rich basin near the Jakhira oasis, where almost a quarter of a million barrels of crude per day was pumped into pipelines bound for the coast before the war.
Germany's Wintershall is the latest firm to have sent a small group of Libyan workers to a cluster of oil fields, where sites jointly operated by U.S. firm Occidental Petroleum Corp and Canada's Suncor Energy Inc are also in the process of restarting.
With Libya's prized crude pumping through the desert to the coastal terminal of Ras Lanuf, workers say the country's largest refinery could restart within days, with around 300,000 barrels of oil from stocks already built up in tanks there.
Workers have been flown in on cargo flights but many pilots are nervous to cross Libya's skies that are still subject to a NATO-enforced no-fly zone.
Yet, hopes are high for a quick recovery.
"We are preparing to bring back all employees, nothing here has been damaged," said Amal field general manager Saad Ali Eshiem.
But fears of an attack loom large and many Libyans are reluctant to leave the safety of their hometowns for remote sites southeast of Sirte, where fighting continues, and few foreign workers have returned.
With sites operating with a fraction of their pre-war workforces, small teams onsite say output will at best reach 50 percent of total capacity without the help of their colleagues.
Oil flows will also depend on the condition of wells and pipes that have not been used for eight or nine months.
Foreign companies contacted by Reuters declined to say when they would redeploy workers to the fields near Jakhira.
Canada's Suncor said last week it was too early to comment on operations at its Amal field (jointly owned with Benghazi-based Agoco) while Occidental declined to comment on its 70,000 bpd Nafoora field also restarting in the area.
Oil fields are on high-alert, and men armed with AK-47 rifles continue to patrol sites day and night, while pick-up trucks mounted with machine guns patrol nearby areas.
As fighters loyal to Libya's interim government continue to battle for control of central parts of the country, it could be months before oil workers lower their guard and the rest of the work force returns.
And while in other areas, off-shore fields operated by France's Total and fields further east operated by Italian oil and gas company Eni have also restarted, Libyan exports are still only trickling back into the world market.
North Africa's fourth-largest producer exported 1.3 million bpd before the war, and since resuming production in September, has sold only a fraction of pre-war output.
On Friday, the OPEC member sold its fourth cargo of crude oil to Austrian energy group OMV and Swiss refiner PetroPlus.
And while firms have been brisk to restart output at fields that escaped the war relatively unscathed, others are already reported to have suffered major damage and some fields remain too dangerous to inspect.
Earlier this week, Reuters reported an engineer had discovered Eni's largest oil field in Libya, known as Elephant, lay in ruins, after volunteering to inspect the site with a squad of fighters.
(Reporting by Jessica Donati; editing by Keiron Henderson)