Brent crude oil prices held their own in Monday trading, remaining about the $50 per barrel threshold after last week's rig-sparked rally.

Global crude oil prices rallied last week after oil services company Baker Hughes posted a market-wide decline in the number of active rigs. Canada posted the largest decline relative terms, though the United States saw the largest in actual numbers with a decline of 242 year-on-year.

Baker Hughes describes the rig count as an active barometer that gauges the health of the exploration and production side of the energy sector.

Brent crude oil prices rallied to around $55 in recent trading, but pulled back somewhat early in the Monday session to around $54.30. Brent has traded below the $50 for most of the year. Futures contracts show trade above the $60 per barrel mark for September.

The price for West Texas Intermediate, the U.S. benchmark, rallied close to the $50 per barrel mark early Monday to trade at $49.50. WTI prices started 2015 at $52.69.

The rally was supported in part by a decision by the United Steelworkers Union to announce a labor strike amid protracted negotiations with refineries, represented by Shell. Monday's trends in crude oil prices were supported in part by word from the U.S. Commerce Department that consumer spending fell 0.3 percent in December despite the low retail price for gasoline.