U.S. President Donald Trump talks to reporters while welcoming NATO Secretary General Jens Stoltenberg to the White House April 02, 2019 in Washington, DC.

The U.S. is overwhelmingly likely to fail in its attempt to completely halt Iran's oil exports, analysts told CNBC, with President Donald Trump eager to avoid rising gasoline prices ahead of presidential elections next year.

As the first anniversary of the U.S. withdrawal from a 2015 nuclear accord between Iran and several world powers approaches, energy market participants are waiting to see whether the Trump administration will extend sanctions waivers on eight countries importing Iranian oil.

Trump has until May 2 to decide whether to issue new waivers to eight governments — China, India, Japan, Turkey, Italy, Greece, South Korea and Taiwan — that were allowed in November to keep buying Iranian oil without facing penalties.

"The U.S. will probably fail to reduce Iranian exports to zero, despite renewed talk from the White House about letting all oil import waivers expire in early May," analysts at Eurasia Group said in a research note published Tuesday.

Given OPEC and non-OPEC production cuts and conditions in Venezuela, "the oil market probably cannot absorb the loss of 1.3 million barrels per day (bpd) of Iranian crude without a significant effect on domestic gasoline prices — a red line for U.S. President Donald Trump," they added.