* FTSEurofirst 300 down 1.2 pct
* BHP Billiton takes $7.2 bln charge on U.S. assets
* Oil and gas sector under pressure as crude drops below $30
* H&M boosted by strong December sales
By Alistair Smout
LONDON, Jan 15 (Reuters) - European shares fell on Friday, knocked by losses in commodity-related stocks as BHP Billiton suffered from a writedown and oil fell below $30 a barrel.
BHP Billiton shed 6 percent, the top faller on the pan-European FTSEurofirst 300, after it said it would write down the value of its U.S. shale assets by $7.2 billion, cementing expectations that it will be forced to cut its dividend for the first time in more than 25 years.
The STOXX Europe 600 Basic Resources index was down 4.4 percent, with Rio Tinto, Glencore and Antofagasta also among top fallers.
All four stocks also suffered from target price cuts by Japanese bank Nomura. Copper has hit a new 6-1/2 year low this week and was set for its second straight weekly loss.
The oil and gas sector was also under pressure, down 2.6 percent. Brent and U.S. crude both fell below $30 a barrel, as markets braced for more oil out of Iran.
"Stocks are being driven by oil, and given that the Iranian sanctions are due to be lifted, that's causing even more nervousness about this glut of oil that we have," said Zeg Choudhry, managing director of LONTRAD.
Concerns over commodities and Chinese growth have marked a rocky start of the year for global markets. Chinese shares closed at their lowest level since December 2014, rocked again by falling oil.
The FTSEurofirst 300 was down 1.2 percent at 1,317.95 points by 0915 GMT, set for its third straight weekly loss.
It fell 6.7 percent last week when China allowed its currency to devalue and is down another 1.7 percent.
"The extreme move in oil is going to keep things volatile ... (and) we probably won't get a real stabilisation until February now," Choudhry said.
Among other fallers, Brenntag dropped 5.2 percent after the chemicals firm was cut to "hold" from "buy" by Deutsche Bank.
"Brenntag's business model is one of our favourites in the space but we remain cautious on the U.S. outlook, given that industrial indicators are weaker since our last update," analysts at Deutsche Bank said in a note.
The top riser was H&M, up 2.6 percent after it posted a rise in sales in December which beat forecasts.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today's European research round-up (Editing by Gareth Jones)