The Brent/WTI spread has historically ranged between $4/bbl and $8/bbl, but it can expand or contract based on factors related to U.S. and international supply and demand conditions. For example, the Brent/WTI spread hit nearly $14/bbl in April 2011 when protests sparked market fears of significant oil supply disruptions in the Middle East.

U.S. crude oil rose nearly 3% on Monday, as the market waited for Israel to strike Iran. Oil prices spiked last week on fears that Israel could hit the Iran's oil industry in retaliation for Tehran's ballistic missile attack.

Global Brent prices settled Monday above $80 a barrel for the first time since August, as the risk of an Israeli response to last week’s Iranian missile strike intensified, raising the potential for disruptions to the Middle East region’s oil supplies.