Saudi Arabia's crude oil exports have been falling in May, according to figures from two companies that monitor the shipments, as a voluntary production cut pledged by the kingdom and other Opec+ producers takes hold after a jump in April.

Opec's top producer boosted crude exports in April by 470,000 barrels per day (bpd) from March, tanker tracker Petro-Logistics' data shows.

Kpler, which also provides oil flow data, pegs April Saudi crude exports at 7.58 million bpd, up 390,000 bpd from March.

The April boost to crude shipments from Saudi Arabia coincided with signs of higher supply from Russia. Both nations - the top two producers in the Opec+ group - last month pledged voluntary production cuts from May to support the market.

"Saudi Arabian crude supply was roughly 500,000 bpd below their production quota in the first quarter of 2023, but that changed in April when volumes surged higher ahead of the voluntary cut in May," Petro-Logistics Chief Executive Daniel Gerber said in an emailed statement.

"While exports were fairly robust in early May, we are seeing signs of reductions coming as the month progresses/as the voluntary cuts take hold."

The Joint Organisatons Data Initative reported that Saudi crude exports were 7.46 million bpd in February, the most recent official figure available.

The Saudi energy ministry did not immediately respond to a request for comment on April exports.

Kpler's data shows Saudi crude exports are likely to average 6.48 million bpd in May, a sizeable drop from April. Geneva-based Petro-Logistics did not give figures for May exports or the April absolute volume.

Opec+ agreements apply to production, not exports. Saudi Arabia told Opec it produced 10.46 million bpd in April, below its quota in the Opec+ agreement.

A Reuters survey also assessed Saudi production in April as below its quota.

The next Opec+ meeting to review output policy is on June 4. -Reuters