UPDATE 1-Exports of Libya's flagship crude stream rise as output hits 1.25 mln bpd

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LONDON, Nov 19 (Reuters) - Loadings of Libya’s largest crude stream are set to rise sharply, after the OPEC member managed to raise output to pre-blockade levels of 1.25 million barrels per day (bpd).

Loadings of Es Sider crude in December were pegged at around 258,000 bpd, a preliminary programme seen by Reuters showed on Thursday.

This compares with 187,000 bpd in the final November programme.

On Wednesday, the country’s National Oil Corp (NOC) said it had restored output to 1.25 million bpd, a level not seen since eastern forces imposed an eight-month blockade in January that choked oil exports.

This compares with around 1.2 million bpd at the end of last week, and around 100,000 bpd in early September.

Last week, NOC chairman Mustafa Sanalla said output could reach 1.3 million bpd within a month.

Libya’s faster than expected recovery has raised alarms among the Organization of the Petroleum Exporting Countries (OPEC) and allies who have been curbing output this year to reduce bloated oil inventories.

Libya is exempt from the cuts and Sanalla said it wouldn’t be joining any production adjustments until output hits 1.7 million bpd. Libya hasn’t managed to produce at this level since late 2008, according to Reuters estimates.

It could be a challenge for Libya to produce significantly more than 1.3 million bpd because repeated shutdowns since a civil war erupted in 2011 and limited investment in infrastructure has curtailed its production capacity.

Prior to 2011, Libya was producing about 1.6 million bpd.

NOC held a meeting with France’s Total Wednesday to discuss ways of raising output further.

In a statement following the meeting, NOC said budgetary constraints were one of the top challenges to developing the oil sector in the country.

It also held a meeting with the Spanish ambassador to Libya on Thursday to discuss energy cooperation, it said. (Reporting by Ahmad Ghaddar; Editing by Edmund Blair and Mark Potter)