"We now expect the OPEC alliance may extend voluntary cuts beyond the second quarter," analyst Natasha Kaneva said in a note.
"Increasing inventories and oil prices below the level needed to cover domestic spending mean caution when considering increasing production."
"The significant anti-seasonal increase in tangible oil inventories in April is worrying," despite itsbestgameforearncryptoHis fundamentals are strong.
This week's fall in oil prices shows that "physical buyers have left the market, and Brent's top is indeed US$90/barrel."
Kaneva maintains its price forecast unchanged and expects prices to be high in the US$80 -90/barrel range in May and then at US$85/barrel.
Citigroup and Morgan Stanley also expect production cuts to be extended.
Christan Malek, head of energy at JPMorgan Chase, takes a different view, arguing that there is a "strong" demand reason for OPEC+ to resume supply.