The price of brent crude oil rose to 70 dollars a barrel on Monday, supported by ongoing output cuts led by OPEC and Russia, and ignoring a rise in U.S. and Canadian drilling activity that points to higher future output in North America.

Brent sweet crude futures, the international benchmark for oil prices, were at 70 dollars per barrel at 0558 GMT, up 13 cents from their last close.

U.S. West Texas Intermediate (WTI) crude futures were at 64.53 dollars a barrel, up 23 cents.

Both benchmarks last week reached levels not seen since December 2014, with Brent touching 70.05 dollars a barrel and WTI reaching as high as 64.77 dollars.

ANZ bank said on Monday that oil prices had recently risen on data that continued to show that the market was tightening.

Oil markets had been well supported by production cuts led by the Organisation of the Petroleum Exporting Countries (OPEC) and Russia which were aimed at propping up crude prices.

The cuts started in January last year and were set to last through 2018, and coincided with healthy demand growth, pushing up crude prices by more than 13 per cent since early December.

But other factors, including political risk, also supported crude.

“Tighter fundamentals are (the) main driver to the rally in prices, but geopolitical risk and currency moves along with speculative money in tandem have exacerbated the move,” U.S. bank JPMorgan said in a note.

Attracted by tighter supplies and strong consumption, financial investors have raised their net long U.S. crude futures positions, which would profit from higher prices, to a new record, the U.S. Commodity Futures Trading Commission (CFTC) said on Friday.

U.S. energy companies added 10 oil rigs in the week to Jan. 12, taking the number to 752, energy service firm Baker Hughes said on Friday.

That was the biggest increase since June 2017. ANZ bank said the jump came “as shale producers quickly reacted to the strong rise in prices in 2018.”

The picture was similar in Canada, where energy firms almost doubled the number of rigs drilling for oil last week to 185, the highest level in 10 months.

The high prices for crude, which is the most important feed-stock in the petroleum industry, have also crimped profit margins for oil refiners, resulting in a decline in new crude orders.