Athens, July 17 : Greek authorities have stepped up controls at the country's ports this week after a new resurgence Covid-19 cases linked to the Delta variant was reported on some of the country's popular islands. During his visit to the port of Piraeus on Friday, Minister of Maritime Affairs and Insular Policy Ioannis Plakiotakis urged people to get vaccinated and thereby win the war against the pandemic, reports Xinhua news agency. "Everything will depend on the course of the vaccination program. We urge people to get vaccinated," the Minister told journalists. Currently, the number of travellers boarding vessels across Greece equals about 60 per cent of the flow registered in 2019, he said, stressing that the authorities' top priority is the safety of the visitors and the locals. "I request once again the cooperation of passengers. We protect ourselves and others around us. We travel safely, so that we can have a good summer," he stressed. On Thursday, Greece's Coast Guard took over from shipping companies the responsibility of inspecting the implementation of public health safety measures before boarding. Passengers aged 12 and above are obliged to present either a vaccination certificate (valid 14 days after having received the second dose), or proof of recovery, a negative PCR (polymerase chain reaction) test taken 72 hours before boarding or a rapid test taken 48 hours earlier. A passenger locator form should also be submitted before boarding. "The vast majority of people have complied," Ministry spokesperson Nikolaos Kokkalas said, reiterating the need for more people to get vaccinated as around half of Greece's total population is still not inoculated. "We try to persuade the crew members to get vaccinated like all passengers in order to ensure the health of the crew, the passengers and the residents of our islands," he said. Officials have sounded the alarm at some popular tourist destinations in the Aegean Sea and have toughened measures at the regional level. Unvaccinated employees in the tourism and catering sectors, including those working on passenger ships, will have to undergo two coronavirus tests per week as of Saturday, Deputy Minister for Civil Protection and Crisis Management Nikos Hardalias said during a press briefing, pointing to the statistics behind the decision. Between July 7-14, the daily infection rates jumped from 77 to 318 on Mykonos; from 24 to 56 on Santorini; and from 9 to 72 on Paros. On the island of Crete, the respective figures were 384-782 in the region of Rethymno and 310-878 around Iraklio. Greek officials continue to urge the public to get vaccinated and to observe the safety measures, which include the wearing of face masks indoors, in order to avoid having to resort to more restrictive measures on local level during the summer. This month, the daily number of new infections across Greece exceeded 3,000 for the first time in four months. /IANS