LONDON- Production at Kazakhstan's largest oil venture, Tengizchevroil (TCO), is back to normal, operator Chevron said on Tuesday, after output was disrupted because of protests last week.

"The workplace environment is stable at Tengiz and production facilities are operating at normal rates," Chevron said in a statement.

Production at Tengiz, Kazakhstan's largest oilfield, was curtailed last week as some contractors disrupted rail services in support of protests taking place across the country. 

Kazakhstan is a major oil producer with output of about 1.6 million barrels per day (bpd) in recent months, and has rarely seen production disrupted by unrest or natural disasters.

But the central Asian country's daily oil and gas condensate production fell 6% in early January from December levels, according to two industry sources and Reuters calculations. 

TCO produces about 700,000 bpd. Trains are used to transport liquefied petroleum gas (LPG), a by-product from the oil extraction, sources told Reuters.

(Reporting by Ron Bousso, Editing by Louise Heavens, Robert Birsel) ((ron.bousso@thomsonreuters.com; +44 (0) 2075422161; Reuters Messaging: ron.bousso.reuters.com@reuters.net))