Oil prices have risen sharply after Iran rejected calls to end support for attacks by Houthi rebels on vessels in the Red Sea and sent a warship to the key trading route.
In the first trading session of the new year, Brent crude rose $1.73, or more than 2%, to $78.77 a barrel on Tuesday, while US West Texas Intermediate crude was at $73.36 a barrel, up $1.71, or 2.4%.
