Oil prices held just below December 2014 highs on Monday, supported by ongoing output cuts led by OPEC and Russia despite a rise in U.S. and Canadian drilling activity that points to higher future output in North America.

Brent crude futures LCOc1, the international benchmark for oil prices, were at $69.89 per barrel at 0308 GMT, up 2 cents from their last close.

U.S. West Texas Intermediate (WTI) crude futures CLc1 were at $64.44 a barrel, up 14 cents from their last settlement.

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

ANZ bank said on Monday oil prices had recently risen “on the back of data continuing to show the market is tightening.”

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

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

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.

Despite the sharp price rises since December, some analysts have been warning of a downward correction.