Britons travelling to the Balearic islands will need to show either a negative PCR test or proof they have been fully vaccinated against the coronavirus, Spain’s prime minister, Pedro Sánchez, said on Monday.

The rules – which come into effect in 72 hours, – were announced two days before the Balearics are due to move on to the UK’s green list for quarantine-free travel, and amid growing concerns over what Sánchez called “the negative evolution” of the virus in the UK.

Spain had planned initially to let British visitors enter the country without the need for a negative PCR test, but pressure has been mounting on the central government following rising case numbers in the UK and clusters of cases in Spain that were traced back to an end-of-year school trip to Mallorca.

“We’ve been seeing a negative evolution of the accumulated incidence in the UK over recent weeks,” Sánchez told Cadena Ser radio. The number of cases per 100,000 people stands at 123 in the UK and 95 in Spain.

“We’re going to apply the same requirements for British tourists in the Balearics that we apply to those from the rest of Europe,” the prime minister added.

“They will need to be fully vaccinated or have a negative PCR test to travel to the Balearics. This will take effect in 72 hours so that tour operators and British tourists can adapt to this new rule.”

The regional government of the Balearic islands – the only part of Spain to be included on the green list – had expressed concerns over rising case numbers in the UK and called for “strict and safer entry controls” for UK visitors.

“We’ve made huge efforts to get here and the state needs to protect the strong health situation in the Balearic Islands,” the regional president, Francina Armengol, tweeted last week.