U.S. West Texas Intermediate (WTI) crude oil futures were trading at $50.81 per barrel at 0011 GMT, up 52 cents, or 1 percent, from their last settlement. International Brent crude futures were at $52.14 a barrel, up 46 cents, or 0.9 percent.

U.S. West Texas Intermediate (WTI) crude oil futures were trading at $50.81 per barrel at 0011 GMT, up 52 cents, or 1 percent, from their last settlement. International Brent crude futures were at $52.14 a barrel, up 46 cents, or 0.9 percent.

Brent crude LCOc1 was at $51.91 per barrel at 0655 GMT, up 39 cents, or 0.76 percent from the previous close. U.S. West Texas Intermediate (WTI) crude CLc1 was up 40 cents, or 0.8 percent, at $50.34 a barrel.

Brent crude oil prices are forecast to average $43/barrel (b) in 2016 and $51/b in 2017. West Texas Intermediate (WTI) crude oil prices are forecast to average about $1/b less than Brent in 2016 and in 2017. The current values of futures and options contracts suggest high uncertainty in the price outlook. NYMEX contract values for January 2017 delivery traded during the five-day period ending October 6 suggest a price range from $37/b to $68/b encompasses the market expectation of WTI prices in January 2017.

Brent crude, the global oil benchmark, rose 0.2% to $51.91 a barrel on London’s ICE Futures exchange. On the New York Mercantile Exchange, West Texas Intermediate futures were trading up 0.1% at $50.21 a barrel.

December Brent crude oil futures LCOc1 were down 42 cents at $52.72 a barrel by 1100 GMT, below Monday's one-year high at $53.73, but off an intraday low at $52.51, while U.S. futures CLc1 were down 43 cents at $50.92 a barrel.

"Higher production from Libya, Nigeria and Iraq are reducing the odds of such a deal rebalancing the oil market in 2017," Goldman analysts said.

Global benchmark Brent crude futures LCOc1 reached a high of $52.57 a barrel, not far off a one-year high of $52.86 a barrel, by 1207, up 64 cents on Friday's close. U.S. futures CLc1 also gained ground, trading at $50.32, up 51 cents.

Brent LCOc1 traded at $52.11 at 1000 GMT, 40 cents down, after touching $52.84 earlier, two cents below the 2016 high. U.S. oil futures traded as high as $50.74 a barrel, a three and a half month high, before falling by 30 cents to $50.14 a barrel. On Thursday they settled at $50.44 per barrel - the first settlement above $50 since June 23.

U.S. West Texas Intermediate (WTI) crude futures were trading at $49.22 per barrel at 0649 GMT, up 53 cents, or 1.1 percent, from their last settlement. In international oil markets, benchmark Brent crude was trading at $51.38 per barrel, up 51 cents, or 1.0 percent.