(Bloomberg) -- The U.K. said it will decide by early next month whether Britons can resume taking international holidays on May 17, while implementing coronavirus testing rules that airlines criticized as too costly.Countries will be rated according to their Covid-19 risk in a traffic light system, the Department for Transport said Friday. At a minimum, travelers will need to buy a two-test package, including a so-called PCR assessment, that typically costs around 220 pounds ($300) per person and can range much higher.“The framework announced today will help allow us to reopen travel safely and sustainably, ensure we protect our hard-won achievements on the vaccine roll-out and offer peace of mind to both passengers and industry,” Transport Secretary Grant Shapps said in an emailed statement.Airline groups welcomed the progress toward a travel restart after a year of Covid-19 restrictions that walloped the industry. Still, they criticized testing requirements they said would put family vacations out of reach for many.Tim Alderslade, chief executive officer of the industry body Airlines UK, called the proposals a “further setback for an industry on its knees.”Start DateThe U.K.’s fast vaccine rollout has driven down cases and given the travel industry its best shot at taking advantage of the summer high season. But without a clear date to restart non-essential travel, airlines remain unable to confidently schedule flights, staff and aircraft requirements.The government has said that May 17 is the earliest day foreign holidays can resume, but officials have warned that a further delay could be required if coronavirus infections continue to surge elsewhere in the world.Different testing and quarantine regimes will be compulsory according to whether a destination is rated green, amber or red, the department said. It’s still too early to say which nations will fall in each category, with a decision coming in early May on that matter and whether the May 17 target can be met.Shapps defended the need for PCR tests that can identify Covid-19 variants and said he’ll look for ways to keep the costs down.“I’m going to work with the travel industry and the private testing providers to drive down that cost,” he said in an interview on BBC Radio 4. “I won’t spare those companies who seem to be profiteering, including potentially removing them from the recommended list.”Traffic Light SystemUnder the new system British residents going on holiday abroad will be required to purchase Covid-19 testing packages and quarantine packages from approved providers, prior to departure, depending on the traffic light rating of their destination. Countries in the safest, “green” category that are in danger of being elevated to amber will be placed on a public watch list so that travelers have advanced warning of a possible change in rating and can plan accordingly.The industry took particular aim at the decision to require a PCR test, which is more accurate but much more expensive, upon return to the U.K. Lateral flow tests cost as little as 5 pounds.“This does not represent a reopening of travel as promised by ministers,” Alderslade said. “The insistence on expensive and unnecessary PCR testing rather than rapid testing – even for low-risk countries – will pose an unsustainable burden on passengers, making travel unviable and unaffordable for many people.”Cost of TestsIn an interview with Sky News, Shapps said he’ll seek innovative ways to lower the testing costs. For example, he said the U.K. might help to provide the faster and cheaper lateral-flow tests people must take before they leave other countries to return to the U.K. The government will also look for ways to lower the expense of testing when they return home from countries in the green category, he said.The U.K. wants to get to a point where travelers can take lateral-flow tests with them in their suitcases so they can take one before their return, Shapps said. At the moment, the requirement for PCR testing when they get home is “an abundance of caution.”Countries will be categorized based on factors including the percentage of their population that have been vaccinated, the rate of infection, the prevalence of Coronavirus “variants of concern” and the destination’s “access to reliable scientific data and genomic sequencing,” the department said. Restrictions will be formally reviewed on June 28, with further reviews no later than July 31 and Oct. 1.New OutbreaksWhile Britain said in February that its rapid vaccination roll-out could allow a resumption of travel as early as May 17, a new wave of Covid-19 outbreaks in mainland Europe has put that target at risk. A second summer lost to the coronavirus crisis would likely trigger a spate of airline failures and bankruptcy filings, alongside a repeat of 2020’s bailouts, job cuts, and jetliner deferrals and cancellations, according to consultants IBA Group.“As it stands, a meaningful restart of aviation is not yet possible under the new system,” Karen Dee, CEO of the Airport Operators Association, said in a statement. “This puts the government’s Global Britain agenda and more than a million jobs supported by aviation and tourism at risk.”(Updates throughout to highlight reaction on costs)For more articles like this, please visit us at bloomberg.comSubscribe now to stay ahead with the most trusted business news source.©2021 Bloomberg L.P.