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LONDON, June 20 (Reuters) - OPEC and non-OPEC oil producers' compliance with a deal to cut global output has reached its highest in May since they agreed on the curbs last year, reaching 106 percent last month, a source familiar with the matter said on Tuesday.
OPEC compliance with the output curbs in May was 108 percent, while non-OPEC compliance was 100 percent, the source said. Another source confirmed compliance by all producers in May was 106 percent.
"This is the highest compliance since the beginning of the deal," one of the sources said.
The Organization of the Petroleum Exporting Countries and allies agreed to cut supply by about 1.8 million barrels per day (bpd) starting in January to get rid of a supply glut. A technical committee of OPEC and non-OPEC producers met in Vienna on Tuesday to monitor compliance with the pact.
The producers agreed at a May 25 meeting to extend the accord until March 2018. But oil has declined sharply since then, with Brent crude falling to a seven-month low near $45 a barrel on Tuesday on persistent over-supply concerns.
With recovering production from Nigeria and Libya - OPEC members exempted from supply cuts due to losses caused by unrest - adding to supplies, some OPEC delegates are questioning whether the agreement is enough.
But oil ministers, including Saudi Energy Minister Khalid al-Falih, are of the view that the market is heading in the right direction and needs time to rebalance.
The panel, which met at OPEC's Vienna headquarters, is the Joint Technical Committee (JTC) established in January to monitor adherence to supply cuts.
Top OPEC producer Saudi Arabia is also a member of the JTC in its capacity as 2017 OPEC president. (Reporting by Reuters OPEC team; editing by Susan Thomas and Jane Merriman)