FTSE 100 drifts as mining, oil shares shift lower

U.K. stocks struggled for direction Friday, with heavily weighted commodity shares trading in the red, but the market kept on course for a weekly gain.

The FTSE 100 UKX, +0.15%  was off 3 points at 6,826.78 and has been darting in and out of positive territory since the open. The London benchmark on Thursday rose 0.2% after a choppy session. Trading volume was lighter than usual that day, with U.S. equity markets closed for Thanksgiving. There will be a shortened U.S. trading session on Friday.

Read: Here’s when markets close on Black Friday

For the week, the FTSE 100 was looking at rise of 0.8%. That would be a third straight weekly advance for the blue-chip benchmark.

GDP growth reading intact: Stocks and the pound didn’t move much after the Office for National Statistics said third-quarter growth in gross domestic product was unchanged from an initial estimate of 0.5% on a quarter-over-quarter basis. It was also unchanged at 2.3% year-over-year. The initial reading released in October was better than anticipated.

Household consumption, the largest category of spending, and business investment each rose in the three months following the U.K.’s June vote to leave the European Union, the ONS said Friday.

“Looking forward, we do still anticipate a mild, but undramatic, slowdown in the U.K. economy. Specifically, we see GDP growth decelerating from 2.0% this year to 1.4% next year,” said Investec economist Chris Hare, in a note. “That is based on the view that we are still seeing a more uncertain post-referendum business investment environment, while we also foresee an impending real income squeeze on households as post-vote falls in sterling begin to push up on imported inflation,” he said.

“However, if the business spending data continue to exceed expectations, the risks to the post-referendum economy might tilt increasingly to the upside.”

The British pound GBPUSD, +0.0241%  eventually crept up to $1.2457, compared with $1.243 ahead of the data. It’s still down from $1.2485 late Thursday.

Movers: AstraZeneca PLC AZN, +2.01%   shares rose 1.1% after the drug maker was upgraded to buy from hold at Liberum.

Mining shares rose earlier in the session as the dollar DXY, -0.30%  pulled back from highs not seen in nearly 14 years. Dollar strength can hurt dollar-denominated metals prices and related stocks. But most of those shares started to drift lower.

Anglo American PLC AAL, -1.75%  shed 1.2%, Fresnillo PLC FRES, -0.88%  moved down 1.2% and Glencore PLC  GLEN, -1.85%  slipped 0.5%. Rio Tinto PLC RIO, -0.05% RIO, -1.08% RIO, +2.42%  pared its gain to 0.3% and Randgold Resources Ltd. RRS, +0.70%   clung to a 0.1% rise.

Oil majors Royal Dutch Shell PLC RDSB, -0.38% RDS.B, +0.00% and BP PLC BP., -0.82% BP, -0.42%  fell 0.8% and 0.4%, respectively, and West Texas Intermediate oil futures CLF7, -2.34%   and Brent crude futures LCOF7, -2.39%  each dropped more than 1%.

“Over the weekend OPEC officials from Algeria will travel to Iran for some closed door meetings. This meeting is really a precursor for OPEC’s meeting with Russia on Monday, which is really a precursor to the official OPEC meeting on Wednesday,” Mati Greenspan, senior market analyst at eToro, wrote in a note.

Investors will look for OPEC to strike a final deal on curb production.

“If everything goes well and all of the OPEC members plus Russia agree on a deal we could see [oil prices] price rise above the current $40 to $50 range,” Greenspan added. “If the deal blows up we could see some very serious consequences in the price and depending on the circumstances some rapid moves for short-term trading.”

Black Friday: Investors will watch for any news from retailers about Black Friday revenue, as they carry out promotions modeled after traditional U.S. post-Thanksgiving shopping deals.

In the U.K., sales are estimated at £2 billion and may swell to £4 billion, as weekend and Cyber Monday sales are included, said Ipek Ozkardeskaya, senior market analyst, at London Capital Group, in a note.

The “sharp depreciation in the pound since the Brexit referendum, rising import prices, hence higher inflation expectations, would encourage U.K. shoppers to take advantage ... to binge-shop before prices climb higher,” she said.

Shares of department store operator Marks & Spencer PLC MKS, -0.60%  swung down 0.2%, Next PLC NXT, -0.28%  was off 0.1% and Dixons Carphone PLC DC., -0.03%  declined 0.2%, paring a deeper loss.