Spain is to restrict arrivals from Europe's Schengen zone and impose a mandatory 14-day quarantine period on all travellers to avoid importing new virus cases, the government said Tuesday.

Both measures come into effect on Friday and will remain in force until May 24 when the state of emergency expires -- or beyond if the measure is extended, the official government bulletin said.

One of the world's worst-hit countries in which the virus has killed nearly 27,000 people, Spain has begun a cautious process of slowly lifting its stringent mid-March lockdown.

The orders are aimed at protecting the rollback that began in earnest in half of the country on Monday and which is due to be completed by the end of June.

"During the rollback period, vigilance and health and hygiene monitoring must be stepped up in respect to all international travellers to avoid any imported (virus) cases," it said.

"Given the global distribution of the virus and working from the principle of precaution, it is necessary that anyone coming from abroad observe a 14-day quarantine period."

Health officials "could make contact to ensure the quarantine is being followed", it warned saying those affected would only be allowed out to buy essentials or for urgent medical care -- always wearing a mask.

The measure will not apply to cross-border workers such as those transporting goods, airline staff and medical personnel as long as they have not been in contact with anyone infected by the virus.

The announcement came as Spain announced another 176 deaths in 24 hours, raising the overall toll to 26,920, while the number of confirmed cases rose over the same period by 426 to 228,030.

"Our situation is changing, the evolution of the epidemic is very good.. but this doesn't mean there's no longer any risk," said Fernando Simon, the health ministry's emergencies coordinator.

"Even if we in Spain manage to stop transmission of the virus, there are going to be many countries around the world where transmission is continuing, which means our biggest risk.. is that of imported cases."

- New limitations within Schengen -

The government also limited those arriving by air and sea from the passport-free Schengen zone which counts 26 member states, four of whom are not part of the EU.

Spain closed its land borders with France and Portugal on March 17 but until now had not imposed any restrictions on Schengen arrivals.

"From May 15, only Spanish citizens, residents, cross-border workers, healthcare professionals or those caring for the elderly will be allowed in, as well as those who can prove an emergency or who are coming for exclusively work reasons," Health Minister Salvador Illa said.

"It is a precautionary measure to avoid anyone with the sickness coming into the country," he said.

Exceptions include airline crews and those working in transportation, with the quarantine requirement to be imposed only on citizens, residents and those citing an emergency.

One group that will be affected by the new restrictions are those foreigners who own a second home in Spain, with the order seeking to "avoid inconsistencies," Simon said.

"It wouldn't make sense for a Spaniard living on the mainland no to be able to travel to his second residence in the Baleares.. while a person living abroad could do it by flying in," he said.

"We think this type of discrimination should be avoided."

The government bulletin said all travel agents, tour operators and transport operators "must inform travellers about the measures at the point of sale" for any destination within Spain.