Iranian hardliners have reinstated about 200 candidates they barred from the 20 February election, but hundreds of reformists remain blacklisted.
Reformists say they plan to keep protesting
About 80 MPs are among those barred by the powerful 12-man Guardians Council, which vets election candidates.
Reformist MPs on Thursday ended a 26-day parliamentary sit-in, but vowed to continue a planned boycott of the vote.
"Nothing has changed. This election is not legitimate, free and fair," said one banned MP, Jafar Kambozia.
The unelected Guardians Council last month barred nearly half of the 8,200 candidates who wanted to run in the election.
IRAN'S REINS OF POWER
Supreme leader Ayatollah Ali Khamenei: Appointed for life, overrides all other authorities (pictured above)
Guardian Council: Half chosen by Khamenei, responsible for vetting election candidates and laws
President Mohammad Khatami: Elected for four years, power can be circumscribed by clerics
Parliament: 290 members introduce and pass laws, subject to approval
The Council reinstated about 1,000 candidates last week following rare intervention from Iran's supreme leader, Ayatollah Ali Khamenei.
Ayatollah Khamenei then asked the Council to review the remaining 2,500 cases.
On Friday, senior conservative cleric Ayatollah Mohammad Emami Kashani defended the Council's decision to uphold the ban on many candidates.
"There might be some mistakes but the Council members did their best and worked hard," he told worshippers.
Without major pro-reform parties taking part in the elections, observers say voter turnout is likely to be low and hardline candidates could easily retake control of parliament, known as the Majlis.