LONDON, Oct 11 (Reuters) - OPEC cut its forecast of global demand growth for oil next year for a third straight month on Thursday, citing headwinds facing the broader economy, and key consuming countries in particular, from trade disputes and volatile emerging markets.
In its monthly report, the Organization of the Petroleum Exporting Countries said world oil demand would increase by 1.36 million barrels per day (bpd) next year, marking a decline of 50,000 bpd from its previous estimate.
The group also cut the estimate for demand in 2019 for its own crude by another 300,000 bpd from last month to 31.8 million bpd, which in turn marks a decline of 900,000 bpd from the projection for 2018.
OPEC said its own production rose by 132,000 bpd in September to 32.76 million bpd, the highest according to the monthly report since August 2017.
Saudi Arabia and Libya increased output last month by 108,000 bpd and 103,000 bpd respectively, more than offsetting the 150,000-bpd decline from Iran to 3.447 million bpd, as reported by secondary sources.
OPEC said Iran told the group its oil output had fallen by just 51,000 bpd to 3.775 million bpd.
The group, led by Saudi Arabia, has pledged to increase output to compensate for the loss of any Iranian supply to U.S. sanctions that come into force next month.
OPEC cut its forecast for growth in non-OPEC oil supply in 2019 by 30,000 bpd to 2.12 million bpd. (Reporting by Amanda Cooper; Editing by Dale Hudson)