Oil costs are climbing to a five-month excessive amid escalating tensions within the Center East

A flare chimney burns behind the oil storage tanks of the Taneco Oil Refining and Petrochemical Complex, operated by Tatneft PJSC, in Nizhnekamsk, Tatarstan, Russia, on Tuesday, March 5, 2019.

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Oil prices rose to their highest since October on Tuesday as investors closely watched threats to new supplies amid an escalating conflict in the Middle East and a Ukrainian drone attack on a major Russian oil refinery.

The USA West Texas Intermediate Treaty Oil for May delivery rose $1.44, or 1.72%, to close at $85.15 a barrel. The Brent The contract for June delivery rose $1.53, or 1.75%, to $88.94 a barrel.

Brent futures have largely traded in a narrow range between $75 and $85 a barrel since the start of the year, but heightened geopolitical risks and robust economic data appear to have led to a rise.

“The new week, month and quarter were greeted with increasing tensions in the Middle East and indirect Iranian involvement,” Tamas Varga, an analyst at oil broker PVM, said in a research note published on Tuesday.

OPEC member Iran has blamed Israel for a deadly airstrike on Monday on its consulate in the Syrian capital Damascus, which reportedly killed seven of its officials.

Tehran vowed on Tuesday to retaliate for the attack, which was seen as a major escalation in the war between Israel and Hamas. According to Sky News, Israel has not declared responsibility and a government spokesman said it would not comment on foreign media reports.

PVM's Varga warned that the possibility of direct Iranian involvement in the Israel-Hamas war could trigger a “regional conflict with plausible implications for oil supplies.”

Ukraine on Tuesday attacked one of Russia's largest oil refineries with a drone strike in the highly industrialized region of Tatarstan southeast of Moscow, about 1,300 kilometers (800 miles) from the front lines of the conflict.

Tatarstan's boss Rustam Minnikhanov wrote in a Google-translated post on Telegram that industrial sites in the cities of Nizhnekamsk and Yelabuga had been attacked by drones.

“There is no serious damage, the technological process of companies is not disrupted,” Minnikhanov said.

Russia – an influential member of the Organization of the Petroleum Exporting Countries and its allies, collectively known as OPEC+ – has been hit by a spate of Ukrainian drone attacks in recent months and has sought to escalate its own attacks on Ukraine's energy infrastructure.

—CNBC's Elliot Smith and Spencer Kimball contributed to this report.