Crude oil futures tumbled at the open Sunday after OPEC decided to boost output. WTI crde (CL1:COM) -3.8% and Brent (CO1:COM) -3.5% dropped more than 3%. Eight members of OPEC+ on Saturday announced a second straight monthly increase of 411K barrels of crude per day for June.

OPEC+ will accelerate oil output hikes and could bring back to the market as much as 2.2 million barrels per day by November, five OPEC+ sources said as the group's leader Saudi Arabia seeks to punish some fellow members for producing above quotas.

The group agreed to raise output in June, a sign that Saudi Arabia and its allies appear to be weary of cutting output and may be trying to appease President Trump, who has pushed for lower prices.