TEHRAN: Iran has approved an extra 1,500 candidates to contest this month's parliamentary election, raising the total number of hopefuls by around a third, an electoral official said Saturday.

The increase came after previously rejected candidates presented new evidence of their credentials, allowing a partial reversal of the mass disqualification of thousands last month.

Those seeking to become one of Iran's 290 lawmakers must first be screened by the Guardian Council, a conservative-dominated committee of clerics and jurists. The vetting procedure is contentious because the February 26 poll is an opportunity for reformists and moderate politicians to make gains against a currently conservative majority in parliament. On January 18, officials said 4,700 prospective candidates had been approved from more than 12,000 original applications. But 6,180 are now eligible, said interior ministry spokesman Hossein Ali Amiri on Saturday, according to official IRNA news agency.

"In no other elections have we had so many approved candidates, which is partly due to the increased number of registrations," he said.

Among those excluded last month were thousands from Iran's reformist movement, a group with little parliamentary representation. On hearing of the rejections, reformists asked President Hassan Rouhani, a moderate cleric with close ties to the reform movement, to intervene and seek changes.

Reformists largely stayed away from legislative polls four years ago in protest at the disputed re-election as president of Mahmoud Ahmadinejad, in 2009. Rouhani is hoping his allies can capitalise in the elections after last month's implementation of Iran's nuclear deal with world powers lifted longstanding sanctions. Reformists have yet to announce how many of their candidates were re-approved. One official said last month that only one percent of its applicants -- 30 from 3,000 -- were deemed eligible but others have said many more would be allowed to stand.