Oil prices have jumped on concerns that the situation in Israel and Gaza could disrupt output from the Middle East.
Brent crude, the international benchmark, climbed by $2.25 a barrel to $86.83, while US prices also rose.
Israel and Palestinian territories are not oil producers but the Middle Eastern region accounts for almost a third of global supply.
Hamas’s assault on Israel was the biggest escalation between the two sides for decades.
Western nations condemned the attacks. A spokesperson for Hamas, the Palestinian militant group, told the BBC that the group had direct backing for the move from Iran – one of the world’s largest oil producers.
Iran denied involvement in the assault at a UN Security Council meeting in New York on Sunday, Reuters reported. But Iranian President Ebrahim Raisi has expressed support for the attack.
On Monday, Israel ordered US oil giant Chevron to pause production at the Tamar natural gas field off the country’s northern coast, which is within range of rocket fire from the Gaza Strip.
The country’s energy ministry, which has closed the field during previous periods of unrest, said there was enough fuel from other sources to meet Israel’s energy needs.
Israel’s largest offshore gas field, Leviathan, continues to operate as normal, Chevron said.
Energy analyst Saul Kavonic told the BBC that global oil prices have risen “due to the prospect of a wider conflagration that could spread to nearby major oil-producing nations such as Iran and Saudi Arabia”.