The slide in oil prices has paused after crude fell more than 70% from its 2014 peak. Now the question is whether the recent rise itself could spark another downward spiral.

U.S. oil prices are up more than 45% from a 13-year low in February, boosted by talks among Saudi Arabia, Russia and other major producers about capping their output.

A temporary reduction in global crude supply following outages in Nigeria and Iraq also helped buoy the market.

On Friday, the International Energy Agency said that oil prices may have bottomed out, and it forecast U.S. output to decline by nearly 530,000 barrels a day this year. The report seemed to support the market’s increasingly bullish mood, pushing U.S. oil prices up 1.7% to $38.50 a barrel.

But this rally could lead to its own demise, many analysts warn. Higher prices will likely encourage shale producers to ramp up output again, muddying any forecasts for shrinking U.S. supply. Shale wells can be drilled and fracked within a matter of months, compared with the years it can take to complete other types of oil wells.