By FARNAZ FASSIHI

When the Iranian film “A Separation” won a Golden Globe award and garnered two Oscar nominations, Iran’s film community hoped the government—which put the film up for awards—would embrace the accolades and give the industry some more breathing room.

Instead, filmmakers have come under greater pressure. Conservative media have trashed the movie as anti-Iranian for its portrayal of social-class differences and economic hardship. Iranian officials haven’t congratulated Asghar Farhadi, the movie’s author and director. Last month, Iran’s Ministry of Culture closed the House of Cinema, a film-professionals guild that ran one of the country’s last remaining independent venues for artistic gatherings.

The closure was part of a larger regime offensive against gatherings and organizations that could galvanize antigovernment sentiment, an effort that has intensified before parliamentary elections on March 2—five days after the Academy Awards ceremony.

The election is shaping up to be a contest among conservatives. Most politicians in Iran’s so-called reformist parties who wanted to run for office, and even some conservatives who were openly critical of the government, were rejected by a government body that vets candidates’ fitness for office. The main reformist parties and the opposition Green Movement have called for a boycott of the vote, saying the election process isn’t democratic.

That has left the conservatives battling each other in the biggest round yet of what has become a bitter, public battle between Supreme Leader Ayatollah Ali Khamenei and Iran’s president, Mahmoud Ahmadinejad.

While Mr. Khamenei once provided the critical support that thrust Mr. Ahmadinjad into the presidency, the two men have fallen out in a power struggle that has played out over the past year. Mr. Ahmadinejad has led an unprecedented behind-the-scenes challenge to the supreme leader, while Mr. Khamenei has worked steadily to clip his wings.

The election pits supporters and loyalists of both men in a fight for influence in the parliament. The intensity of the infighting has led to new crackdowns on social groups and organizations, some of which have steered well clear of direct involvement in politics or Tehran’s power struggles.

The government appears particularly sensitive about independent and volunteer organizations, such as unions and guilds and nongovernmental organizations, that offer a platform for public gatherings, analysts say. After protesters disputed the results of Mr. Ahmadinejad’s 2009 re-election, the journalists’ and workers’ guilds were shut down, and the lawyers’ union was also targeted.

NGOs have been told that they can’t host events with more than 10 people, a stricture that extends even to annual charity fund raisers for the Persian New Year.

Meanwhile, dozens of journalists, bloggers and activists have been arrested in the past few weeks, an acceleration of the normal pace of detentions, Iranian human-rights groups and activists said. The Supreme Court has upheld the death sentences of at least three activists, including Iranian-Canadian Web developer Saeed Malekpour.

Even as “A Separation” has garnered increasing international acclaim, Iranian authorities have distanced themselves from the movie, which is nominated for Academy Awards in the international film and original screenplay categories.

The film community is particularly up in arms over the culture ministry’s January decision to close the House of Cinema after 20 years of operation. The government this month sealed shut the film-professional guild building and has confiscated all of its properties.

On Jan. 30, film-industry members submitted a petition, with 2,000 member signatures, opposing the closure. Supporting them was the writer and director of “A Separation,” Mr. Farhadi, who has used his new celebrity status to publicly plead with authorities to keep the House of Cinema open.

Meanwhile, the Ministry of Culture and information held a conference this month on “Hollywoodism and Cinema” to instruct Iranian filmmakers how to avoid what it called “the Zionist regime’s influence.”

The government’s alternating support and dismissal of Mr. Farhadi, a well-known Tehran-based director who has worked within the guidelines of the Islamic Republic, showcases a divided conservative leadership, with some Iranian officials favoring a softer approach to social freedoms while others take a more extremist stance.

The ministry said it closed the guild because it wasn’t appropriately registered.

Other officials were more blunt. “The House of Cinema has turned into a secret den of suspicious political activity against the Islamic Republic and must be shut down,” said parliamentarian Tayabeh Safaieh.

A parliamentary committee upheld the ministry’s decision to dissolve the guild. After the guild filed a complaint in court, the judge threw out the case in late January.

Iranian cinema poses a particular problem to the government “because of its ability to show aspects of Iranian society to the outside world, and because of its popularity at home,” said Hamid Dabashi, a Columbia University professor of Iranian studies and an expert on Iran’s cinema.

Mr. Farhadi has largely operated within government rules, though he had a run-in with the authorities while making “A Separation,” a film about the collapse of a Tehran couple’s marriage that offers a broad view of the rifts of Iranian society. Mr. Farhadi’s permit was temporarily suspended after he spoke during a ceremony at House of Cinema in support of a filmmaker jailed for his support of an opposition movement.

Most Iranian officials have refrained from congratulating Mr. Farhadi, even after the movie swept the awards at the government film festival last year. Iran’s semiofficial news agencies have disparaged the overseas success of the film, calling it anti-Iranian. Its cast has been criticized for being un-Islamic.

Yet the overseas success of “A Separation” has improved its performance in Iranian theaters, where the film had been a box-office hit and theaters extended its run after the movie won awards at international festivals.

Meanwhile, the closure of the House of Cinema has put new restrictions on Iran’s robust film industry.

“We have no job security because our creativity and inspirations are constantly under attack,” said a 42-year-old female director of short films. “I work within a very limited creative framework because of all the red lines and now gathering with our colleagues to talk and screen movies is suddenly illegal.”