LONDON (Reuters) -Oil prices extended gains on Monday, with Brent nearing $80 to build on last week's steepest weekly jump since early 2023, driven by fears of a wider Middle East conflict and potential disruption to exports from the major oil-producing region.

Brent crude futures rose $1.11, or 1.4%, to $79.16 a barrel by 0839 GMT. U.S. West Texas Intermediate crude futures jumped $1.28, or 1.7%, to $75.66.

Brent climbed by more than 8% last week while WTI soared by 9.1% on the possibility that Israel could strike Iranian oil infrastructure in response to an Iran's Oct. 1 missile attack on Israel.

The potential escalation of the conflict has countered mounting demand-side pressures, said Priyanka Sachdeva, analyst at Phillip Nova.

Rockets fired by Iran-backed Hezbollah hit Israel's third-largest city, Haifa, early on Monday. Israel, meanwhile, looked poised to expand ground incursions into southern Lebanon on the first anniversary of the Gaza war, which has spread conflict across the Middle East.

That spread has raised fears that the United States, Israel's superpower ally, and arch-foe Iran will be sucked into a wider war.

ANZ Research, however, expects any immediate on supply to be relatively small.

"We see a direct attack on Iran's oil facilities as the least likely response among Israel's options," it said, noting the buffer provided by producer group OPEC's 7 million barrels per day of spare capacity.

The Organization of the Petroleum Exporting Countries (OPEC) and allies including Russia, known collectively as OPEC+, are due to start raising production from December after cutting in recent years to support prices because of weak global demand. 

OPEC+ has enough spare oil capacity to offset Israel knocking out Iranian supply, but it would struggle if Iran retaliates by attacking installations of neighbouring Gulf nations, analysts have said.

When the Middle East conflict began a year ago, Brent stood at $88.15, but prices are now about $10 lower.

"While nothing can touch the emotion that the conflict has brought to the oil community, it has been well and truly smothered by macroeconomic considerations that have thwarted any idea of an increase in global demand," said John Evans of oil broker PVM.