Sweden's transport authority Monday halted direct flights to and from Iran on the advice of health officials who said Tehran was "not in control" of the outbreak of the new coronavirus on its soil.

The Swedish Transport Agency announced it was temporarily suspending the flight permits of Iran Air -- currently the only airline flying directly between Iran and Sweden -- saying they were responding to a request by Swedish health officials.

"We trust in the competence and expertise of the Public Health Agency of Sweden," Simon Posluk, head of the department for maritime and air traffic at the transport agency, said in a statement.

Sweden has 14 confirmed cases of the virus, including two who had travelled to Iran and four cases traced to those two travellers, according to newspaper Expressen.

The Middle Eastern country has reported 1,501 cases, including 66 deaths in total.

"To continue to take in large groups of passengers from Iran under present circumstances would severely complicate the work to limit the spread of COVID-19," Johan Carlson, director of the Public Health Agency of Sweden, said in a statement.

It added that "responsible authorities in Iran are not in control of the situation" and it feared the spread of the virus in Sweden.

Speaking to AFP, Carlson said the agency was not planning any similar measures for other airlines flying to other heavily affected countries.

The agency did not ask for any bans of flights to and from China, which Carlson said was because they had better working relationships with Chinese authorities and airlines.

"This is a very exceptional situation and it goes back to that we are not really confident in what's happening in Iran today," Carlson said.

Iran Air had until been flying weekly to Gothenburg and two flights a week to Stockholm.

Stockholm last week advised against all non-necessary travel to Iran.

Swedish health authorities also raised the risk assessment level for a general spread of the virus from "low" to "moderate" on Monday, and said the risk that more cases would emerge was "very high."