(Bloomberg) -- Iceland’s government may soon announce a tightening of the rules for travelers to the island following criticism to its open borders policy amid a resurgence in Covid-19 cases.

Among the measures being proposed by the country’s chief epidemiologist are double testing and a mandatory quarantine of 4 to 6 days for foreign tourists and Icelanders returning from their holidays abroad.

Iceland introduced coronavirus tests for anyone arriving at Keflavik Airport on June 15 in an effort to salvage its tourism industry, the country’s main export. Travelers from countries considered safe, such as Germany or Denmark, were exempted from the tests a month later.

The policy, which replaced a mandatory quarantine for all visitors, did little to encourage tourism. In fact, foreign tourist numbers were down 80% in July from a year ago. The development drew criticism from several economists, who accuse the government of placing the interests of the travel industry above the interests of the economy as a whole.

After a period of no new cases, a total of 106 people have tested positive for coronavirus during the past weeks, prompting Norway to add the island to its high-risk list.

“It would be more efficient for society if the rules on entry at the borders were tightened.” Tinna Laufey Asgeirsdottir, a health economics professor at the University of Iceland, said in an interview in Reykjavik.

Asgeirsdottir takes issue with the government’s policy of subsiding the airport tests. Visitors were initially tested for free, but were later charged $100. The price has since come down, to around $66. The professor argues that when intangibles such as health and time lost due to quarantines are taken into account, those tests should be priced at several hundred dollars each at least.

According to Gylfi Zoega, an economics professor at the same university, the costs to the economy from a domestic outbreak caused by higher tourist flows would be “multiple the gain from those visits,” he wrote in an article published by local paper Morgunbladid.

Prime Minister Katrin Jakobsdottir says the border rules are aimed at protecting society as a whole.

“In my mind there are two things that matter: On the one hand health and disease prevention, but also keeping society afloat. Part of that is facilitating travel in a free society and that does not apply only to tourism,” she told Morgunbladid.

Still, a tightening of the rules cannot be excluded, she said.

An announcement is expected in the coming days.

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