LONDON - European carbon emissions futures rose to a one-month high on Thursday, as investors bought up permits as prices broke a key resistance level.

EU Allowances for delivery in December rose 41 cents or 3.13 percent to 13.50 euros ($19.63) a tonne at 1531 GMT, after hitting a one-month high of 13.59 euros. Volume was heavy at 7,575 lots traded.

There was purely technical buying when we breached a 13 euro resistance level, an emissions trader said.

Dec-10 EUA prices broke above the 50-day moving average for the first time since December 17.

EUA prices at those levels are tough to explain fundamentally, another trader said.

Prices started to rise from early trade, outpacing the broker market, which typically trades in near lockstep with the exchange-traded market, brokers said.

The (exchange-traded) market was 5-10 cents ahead of the broker market at one point, one broker said.

It's not clear who was buying ... they could be marking their intentions or it could have just been a fat finger.

Traders said it was difficult to see who was on the buy side because most of the volume was being traded over the European Climate Exchange, rather than over-the-counter between brokers.

Spot EUAs trading on BlueNext were up 41 cents at 13.33 euros.

U.S. crude oil futures rose to near $80 a barrel on Thursday after dipping to a 2010 low the previous day as expectations for rising demand growth in the world's top energy consumer the United States shored up prices.

German Calendar 2011 baseload power on the EEX rose 28 cents at 50.40 euros per megawatt hour.

Benchmark CERs rose 30 cents or 2.64 percent at 11.68 euros a tonne, setting the EUA-CER spread at 1.82 euros.