[NEW YORK] Oil extended declines after Saudi Arabia's deputy crown prince said the kingdom will only freeze production if Iran and others follow suit and Russia's oil output set a post-Soviet high in March.
Futures declined as much as 1.6 per cent in New York after a 4 per cent drop on Friday.
With producers scheduled to meet in Doha this month to complete an accord on capping output, Saudi Arabia's Mohammed bin Salman signaled in an interview with Bloomberg that if any country raises output, the kingdom will also boost sales.
Russian production of crude and a light oil called condensate rose 2.1 per cent in March to 10.912 million barrels a day.
West Texas Intermediate for May delivery dropped as much as 57 US cents to US$36.22 a barrel on the New York Mercantile Exchange, and traded at US$36.35 at 9.44 am Sydney time.
The contract fell US$1.55 to US$36.79 on Friday. Total volume traded was about 24 per cent below the 100-day average.
Brent for June settlement lost as much as 1.1 per cent to US$38.25 a barrel on the London-based ICE Futures Europe exchange.
The global benchmark crude traded at a 54 US-cent premium to WTI for June delivery.