It was not immediately clear what the reason was for thesharp fall in daily production.
"It should be maintenance," - one source said, but addedthat it was not planned.
North Caspian Oil Consortium (NCOC), the operator of theKashagan oilfield, has not answered a request for comment.
Oil production at Kashagan reached 300,000 barrels per dayin January this year, while a rise in output to 370,000 barrelsper day is expected during 2018.
Kashagan crude is exported via the
The Kashagan consortium includes Kazakh state oil firmKazMunayGaz, Eni, ExxonMobil, RoyalDutch Shell, Total,