The only reformist candidate in Friday's presidential election in Iran, Mohammad Reza Aref, has withdrawn from the poll.
Mr Aref said former president Mohammad Khatami, the head of the reformist movement, had asked him to withdraw.
There have been recent calls for Mr Aref to quit in favour of moderate candidate Hassan Rowhani.
The BBC reports most of the six remaining candidates in the poll are conservatives close to Supreme Leader Ayatollah Ali Khamenei.
Conservative Gholam Ali Haddad Adel withdrew his name on Monday, urging people to vote for a conservative candidate though he did not endorse any individual.
The original eight candidates for the elections were approved by the Guardian Council from a list of more than 600 hopefuls.
The election is the first since 2009, when reformists disputed the re-election of Mahmoud Ahmadinejad.
Accusations of vote-rigging led to protests that saw the deaths of at least 30 people and the arrests of more than 1000.
Two reformist candidates are still under house arrest.
Mr Ahmadinejad is constitutionally banned from standing for a third term as president.