Eleven non-OPEC oil producers that joined a global deal to reduce output to boost prices delivered 64 percent of promised cuts in February, an industry source said on Friday, still lagging the higher levels of OPEC itself. The Organization of the Petroleum Exporting Countries (OPEC), Russia and other producers agreed to cut production by 1.8 million barrels per day (bpd) from Jan. 1 to boost prices and reduce a supply glut. Compliance numbers were reviewed at a meeting in Vienna on Friday comprised of officials from countries monitoring adherence to agreed output levels — OPEC members Kuwait, Venezuela, Algeria plus non-OPEC Russia and Oman. Russia plans to step up its adherence, saying on Friday that it will cut output by the full amount it had pledged — 300,000 bpd — by the end of April and will maintain that level until the deal expires at the end of June. […]