LONDON, June 12 (Reuters) - Global oil demand will peak by 2029 and begin to contract the next year, the International Energy Agency said on Wednesday, while oil supply capacity is due to vastly outpace demand by the end of the decade.

The Paris-based energy watchdog sees supply capacity hitting nearly 114 million barrels per day (bpd) by 2030, or a full 8 million bpd above projected demand in its annual oil report.

"This report's projections, based on the latest data, show a major supply surplus emerging this decade, suggesting that oil companies may want to make sure their business strategies and plans are prepared for the changes taking place," IEA Executive Director Fatih Birol said. (Reporting by Noah Browning; editing by Jason Neely)