A worker adjusts a valve of an oil pipe in Zubair oilfield in Basra, Iraq.

A dramatic escalation of geopolitical tensions will most likely result in an unplanned oil supply shortage in the Middle East, energy analysts told CNBC on Tuesday, elevating the likelihood of another spike in oil prices.

International benchmark Brent crude rose to its highest level since September in the previous session, briefly climbing above $70 a barrel, as U.S. West Texas Intermediate (WTI) surged to its highest value since April.

The gains follow intensifying fears about the prospect of retaliatory action from Tehran, after the U.S. killed a top Iranian general late last week.

"The consequence one can draw from the latest chapter of the U.S.-Iran relationship is that the geopolitical risk premium is more likely to turn into unplanned supply shortage than disappear," Tamas Varga, senior analyst at PVM Oil Associates, said in a research note published Tuesday.

"The only questions are when and in what form," Varga said.