Kazakh oil exports via the Caspian Pipeline Consortium (CPC) system fell to 5.2 million tonnes in September, from 5.7 million tonnes in August, owing to scheduled maintenance at the Karachaganak field, three oil industry sources close to the matter told Reuters.
Overall oil throughput via CPC declined to six million tonnes (1.59 million barrels per day) in September, from 6.28 million tonnes (1.6 million bpd) a month earlier, the people said.
CPC does not comment on its commercial operations.
CPC reduced oil loadings between January 1 and September 25 to nearly 50 million tonnes, down four million tonnes from the corresponding period last year.
Supplies via CPC, which carries more than 80 per cent of Kazakhstan's oil exports, have fallen because of the nation's lower crude production after an accident at the Tengiz field in January and maintenance at Karachaganak in September.
Oil loadings at CPC's marine terminal, meanwhile, were suspended repeatedly after drone attacks on tankers near the consortium's terminal at Yuzhnaya Ozereyevka, near Novorossiysk.
CPC shareholders include Russia with a 31 per cent stake, Kazakhstan with 20.75 per cent, Chevron with 15 per cent and a number of private companies.
(Reporting by Reuters Editing by David Goodman)