Ryanair Holdings Plc said the U.K.’s intention to quarantine visitors for 14 days is unscientific and unenforceable, as the carrier announced plans to resume almost 1,000 flights a day starting in July.

The Irish low-cost airline, which has grounded most of its fleet since late March, said it would institute passenger temperature checks, require masks and prohibit lines for toilets as it restarts about 40% of its flights. Lavatories will be made available on request, Ryanair said in a statement.

“Ryanair is opposed to ineffective non-scientific measures such as a two-week quarantine, which is completely unenforceable and non-science based,” it said in an emailed response to questions, after U.K. Health Secretary Matt Hancock said Britons were unlikely to be able to travel abroad this summer. “We expect the public will largely ignore it.”

The comeback for European air travel is dependent on the lifting of government restrictions on flights within Europe. While the European Commission is preparing recommendations for removing border controls, the Ryanair tussle highlights the conflicting priorities that could make the reopening a bumpy one.

Within the European Union, each nation sets its own rules on entry. The U.K., which just left the bloc but remains a major hub for flights in the region, plans a 14-day quarantine on incoming travelers that executives have decried as tantamount to a ban.

Read more: U.K. Quarantine Upends Airline Plans for Return to Flight

“It is unlikely that big, lavish international holidays are going to be possible this summer,” Hancock said in an interview with ITV Tuesday. “I think social distancing of some kind is going to to carry on.”

Spain’s tourism industry, a key driver of the economy, was also dealt a potential blow when the government decreed this week that all people arriving from abroad will be subject to a mandatory 14-day quarantine in “their homes or lodgings.” The measure will stay in force until the current state of emergency is lifted.

Ryanair Chief Executive Officer Michael O’Leary, meanwhile, has also railed against state-aid plans, and this week challenged a French bailout of Air France-KLM.

Ryanair gained as much as 3.8% in Dublin trading. The stock has tumbled 38% this year.

The carrier said it would restart flights from most of its bases, and will offer seats starting from 20 euros ($21.60) one-way. Service will feature fewer checked bags, online check-ins and boarding passes that can be downloaded to smart phones, the airline said.

Coordination Plans

The U.K. quarantine casts doubt on the reopening plans of other grounded European airlines as well. British Airways owner IAG SA has said it will have to review its goal to gear back up starting in July.

The International Air Transport Association has called for governments to take a coordinated approach to reopening in Europe, while acknowledging the challenges given that different countries have different rates of infection.

The EU recommendations, expected Wednesday, are part of a “tourism package” of non-binding guidelines covering everything from health measures to travel vouchers. The EU’s digital chief, Margrethe Vestager, told lawmakers last week that digital contact-tracing apps might “enable at least some traveling during the summer.”