Iran's reformist political factions on Wednesday called on the constitutional watchdog to reverse its decision to disqualify large numbers of moderates and reformists from running in next month's parliamentary elections.

Nine reformist political parties issued a statement noting that only 30 of the 3,000 reformist candidates fielded across the country were allowed to run by the Guardian Council, a watchdog dominated by hard-liners.

Ayatollah Ahmad Jannati, the head of the council, was quoted by the semiofficial ISNA news agency as saying the body "will not be influenced by pressure."

But his deputy, Siamak Rahpeik, said it's likely that up to 15 percent of those disqualified from running will be reinstated during the reviewing process. His comments were posted on the council's website.

The Feb. 26 election will be a contest between moderate President Hassan Rouhani's supporters and his hard-line opponents. Reformists and moderates hope to form a coalition once their candidates survive the screening process. Hard-liners and conservatives are split into several groups, making them more vulnerable.

Iran's Supreme Leader, Ayatollah Ali Khamenei, hinted at a possible reversal to the Guardian Council decision when he told State TV that "enthusiasm" should be drummed up ahead of the elections to increase voter turn-out. However, he said those who don't have faith in the ruling system should not be allowed to hold office.

"Nowhere in the world do decision-makers allow those who have no faith in the system to run," he said.

Barring moderates from running is seen as a tactic by hard-liners worried that Rouhani's success in lifting sanctions under a landmark nuclear deal with world powers will give moderates an electoral boost.

Of over 12,000 hopefuls who applied to run in the February parliamentary elections, around 4,700 have been approved by the Guardian Council, which is responsible for vetting candidates.

While some hard-liners and conservatives have also been barred, reformists have been most affected. Many were disqualified because they were not seen to be sufficiently loyal to the ruling system, as defined by hard-line council members.

Rouhani has vowed to use all his constitutional powers to reinstate those barred, but it's not clear how he will be able to influence the process.

"It's likely that political lobbying will reverse a limited number of disqualifications, but I doubt that there will be widespread reversal," prominent conservative analyst Amir Mohebian said.

The council is now studying complaints from those barred.

Reformists registered in large numbers, hoping that many will survive the screening process even if their best known figures are disqualified. Now they are expressing shock and frustration.

"This is the biggest number of disqualifications in (Iran's) history," said one prominent reformist, Hossein Marashi. But he added that reformists won't boycott the vote. "We will stay to fight because we don't want extremists to grow," he said.

The disqualification of reformist candidates could dash hopes that Rouhani allies will dominate the next parliament. The 290-seat house is currently dominated by conservatives.