Top Russian oil producer Rosneft posted a 13% rise in half-year net profit today to 432 billion roubles ($7.22 billion) which it said was helped by tight cost controls.

Russian oil firms have faced Western sanctions over Ukraine which have impeded their global trade and complicated financing.

"Rosneft was under an unprecedented pressure of adverse external factors and unlawful sanctions," chief executive Igor Sechin said in a statement.

Russia saw an exodus of western businesses following the start of what Moscow calls a "special military operation" in Ukraine on February 24.

BP announced in February it was abandoning its 19.75% stake in Rosneft.

Rosneft said oil sales in the January-June period increased by 5.7% year on year, while its debt dropped by 12% compared to the beginning of the year.

"Thanks to high operational efficiency and appropriate management decisions, we were able to ensure business continuity and demonstrate stable results," Sechin, a long-standing ally of President Vladimir Putin, added.

Rosneft accounted for around half of BP's oil and gas reserves and a third of its production.

In June, Sechin said BP still remained its largest private shareholder despite the withdrawal announcement.

Sechin said at the time that BP's dividend would be transferred to special accounts, without elaborating. Russia has imposed capital controls and restricted cross-border transfers of foreign currencies to weather Ukraine-related sanctions.

Rosneft said today that BP is still entitled to a part of more than 441 billion roubles ($7.4 billion) for 2021.

"1H 2022 financial results form a solid basis for interim dividends payment and a further growth of total payments for 2022," it said.

Rosneft said first-half hydrocarbon production reached 4.85 million barrels of oil equivalent per day, a 1.5% increase from the same time last year "in a comparable perimeter" excluding assets disposed of in 2021.