Oil prices were steady on Friday as the start of supply cuts by Saudi Arabia and Abu Dhabi supported the market, but doubts that all producers will implement output reductions agreed in a landmark deal last year kept markets from rising further. 

Brent crude futures, the benchmark for international oil prices, were trading at $56.85 per barrel at 0238 GMT, down 4 cents from their close the previous day. 

In the United States, West Texas Intermediate (WTI) crude futures were at $53.74 a barrel, two cents below their last settlement. 

"Brent oil may approach a support at $55.43 per barrel, following its failure to break a resistance at $57.50," said Reuters technical commodity analyst Wang Tao.