Iranian Supreme Leader Ayatollah Ali Khamenei called on those elected to parliament and the important Assembly of Experts to act in the interests of Iran and stand against the influence of outsiders.
Final results from Saturday's election are expected Monday or Tuesday, but unofficial tallies show reformists and moderates winning all 30 parliamentary seats in the capital, Tehran, in what would be a resounding vote of confidence for President Hassan Rouhani. Hardliners were poised to lose considerable ground in the 290-seat legislature, but were winning areas outside of major cities.
Iran is emerging from years of international sanctions imposed because of allegations it was working to develop nuclear weapons.
The state-run IRNA news agency quoted Khamenei saying development is the country's top goal.
"Nominal development without independence or national dignity is not accepted," he said.
'Time to open a new chapter'
IRNA quoted Rouhani saying Saturday the election has given the government more credibility and clout.
"The competition is over. It's time to open a new chapter in Iran's economic development based on domestic abilities and international opportunities," the official IRNA news agency quoted him as saying.
The president made last year's nuclear agreement with a group of world powers a key objective of his administration and the outcome could be interpreted as a comment on the level of support for his policies.
The final results may also provide the first clue as to whether key Western proponents of the deal will receive what they hoped for: a more open, moderate Iran.
Rouhani and former president Akbar Hashemi Rafsanjani also are leading the race for membership in the Assembly of Experts. The influential body monitors the work of Supreme Leader Khamenei, who has final say on Iran's foreign policy, and could choose the next supreme leader.View full gallery
Election test of nuclear deal
The vote was the first election since the country's nuclear deal with world powers took effect.
The final results may provide the first clue as to whether key Western proponents of the deal will receive what they hoped for: a more open, moderate Iran.
The outcome could be interpreted as a comment on the level of support for the policies of Rouhani, who is up for re-election next year. Rouhani has made the nuclear agreement a key objective of his administration.
Newspapers reported a huge turnout at the polls Friday, including many young voters.
Polls remained open much later than scheduled, in some cases. State television showed long lines both in Tehran and in polling places around the country.
About 55 million Iranians were registered to cast ballots for members of the conservative dominated 290-seat parliament as well as the 88-member Assembly of Experts.