At the end of a brutal week, oil prices surged Friday morning — jumping back above $31 a barrel.
Prices rose 4.2% Thursday to settle at $29.53 a barrel. That was the biggest one-day percentage gain since October 28.
Stock markets around the world responded as commodities and energy shares shot higher. Asian markets were buoyed by the Nikkei, which jumped 5.8%. The Hang Seng closed 2.9% higher, while shares in Shanghai rose 1.2%.
In Europe, the main indexes jumped between 2% and 3%.
Shell is up 6% and BP is up 4% in London trading.
Still, oil prices are still down about 20% this year and 73% below the June 2014 peak of $107.73.