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LONDON/MOSCOW, May 15 (Reuters) - Black Sea CPC Blend crude oil exports are pencilled in at around 1.6 million-1.7 million barrels per day (bpd) in June, five trading sources with knowledge of the month's loadings told Reuters.

At that level, loadings will be higher than the approximately 1.5 million bpd scheduled for export in May.

The bulk of CPC Blend exports - around 90% according to trade sources - comes from Kazakhstan, and the remainder from Russian production.

Kazakhstan's oil output has become a main point of contention inside the OPEC+ group, as it has repeatedly exceeded its production quotas in the last year.

Despite that, Kazakhstan's energy ministry said earlier this month that it is committed to the OPEC+ agreement.

CPC Blend loadings were scheduled slightly lower on the month in May because of planned three-day pipeline maintenance towards the end of the month.

The Caspian Pipeline Consortium (CPC) does not comment on monthly exports through its system.

The CPC pipeline, which carries more than 80% of all Kazakh oil exports, connects the Tengiz field in western Kazakhstan and a number of others with the CPC marine terminal in Yuzhnaya Ozereyevka near Novorossiisk port.

The shareholders of the CPC are Russia, which owns 31%, Kazakhstan (20.75%), U.S. oil major Chevron CVX.N (15%), ExxonMobil XOM.N subsidiary Mobil Caspian Pipeline Company (7.5%) and other companies.

(Reporting by Robert Harvey and reporters in Moscow; Editing by Kevin Liffey, Elaine Hardcastle)

((Robert.Harvey@thomsonreuters.com; +447552256587;))