* FTSEurofirst 300 index down 0.2 pct
* Commodities shares track weaker oil, metals
* UCB, BNP Paribas, Natixis up after results
By Atul Prakash
LONDON, July 31 (Reuters) - European shares fell slightly after hitting a one-week high on Friday, with commodity stocks leading the market lower after prices of crude oil and major industrial metals dropped on supply-demand concerns.
The European oil and gas index fell 1 percent as oil prices fell after producers' cartel OPEC indicated there would be no output cuts despite a huge global oversupply, while the STOXX Europe 600 basic resources index was down 1.8 percent after copper fell on lingering worries about the metals' demand in top consumer China.
"Concerning China, all eyes are on the release of tomorrow's important manufacturing and non-manufacturing PMIs. Further indications that the economy is still not anywhere close to turning the corner could certainly spook Chinese stocks again," Markus Huber, senior analyst at Peregrine & Black, said.
A sharp sell-off in Chinese shares over the past weeks have stoked concerns about a growth slowdown in the world's second-biggest economy.
Shares in BP, Statoil, Anglo American and BHP Billiton fell 1.2 to 2.0 percent.
Antofagasta slumped 4.7 percent, also under pressure after Goldman Sachs cut its target price for the stock of the company, which is buying half of Barrick Gold's Zaldivar copper mine for $1 billion in cash.
The FTSEurofirst 300 index of top European shares was down 0.2 percent at 1,567.74 points by 1045 GMT after rising to a one-week high of 1,575.11 points earlier in the session on the back of some positive earnings updates.
UCB surged 6.8 percent, the top gainer in the pan-European FTSEurofirst 300 index, after the Belgian pharmaceutical company raised its 2015 forecasts as sales of its three major upcoming drugs propelled first-half earnings by more than expected.
BNP Paribas gained 2.7 percent after its revenue rose nearly 16 percent in the second quarter, while Natixis was up 2.8 percent after reporting a 5 percent rise in net income.
"Overall, the results so far have been pretty good, with the banking sector putting in some good numbers as well," said Clairinvest fund manager Ion-Marc Valahu.
Airbus rose 3.7 percent after posting a 6 percent rise in first-half core operating profit.
According to Thomson Reuters StarMine, nearly half of the STOXX Europe 600 companies have announced results so far, of which 53 percent have met or beaten analysts' forecasts.
On average, 48 percent companies beat analyst EPS (earnings per share) estimates in a quarter. Second quarter earnings are expected to grow by 5.7 percent from the corresponding quarter of the previous year.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today's European research round-up
Additional reporting by Sudip Kar-Gupta; Editing by Tom Heneghan