This file photo taken on February 26, 2020 shows Hans Kluge, WHO regional director for Europe, as he gives a press conference in Rome. (ALBERTO PIZZOLI / AFP)

COPENHAGEN - The World Health Organization (WHO) Regional Office for Europe raised the alarm Thursday on the disturbing increases in the "incidence and numbers" of coronavirus infections in eastern European countries  despite weeks of decline in other European nations.

The number of European countries showing significant increases in cumulative incidence has more than tripled from six to 21 countries. 

Hans Kluge, WHO regional director for Europe

"In the past month, the number of European countries showing significant increases in cumulative incidence has more than tripled from six to 21 countries," said Dr Hans Kluge, WHO regional director for Europe, during a regular virtual meeting hosted in Copenhagen.

ALSO READ: WHO drawing up plans for 'fair, equitable' access to virus vaccine

Kluge's remarks dispelled any complacency after WHO statistics showed that the situation in Europe had "stabilized at around 17,000 to 20,000 cases per day on average due to weeks of cases declining in other countries."

"COVID-19 is still in a very active phase in many countries. It is crucial that we continue to recover and rebuild following the lockdown," said the WHO official.

Kluge emphasized the need to remain diligent and lift restrictions with care, citing the reopening of schools in a few countries that resulted in local flare-ups.

ALSO READ: Virus: Russia says it already uses dexamethasone to treat patients

In his oft-repeated call to countries in the region, Kluge asked them to strengthen the preparedness and readiness of their emergency services and routine health system delivery, because he was "hoping for the best but preparing for the worst" of a likely resurgence of COVID-19.

"We are not out of the woods. Lockdowns and social distancing have gained us time," he said, reiterating that "the risk remains high across all countries."

READ MORE: Brazil surpasses UK in virus deaths, now 2nd in world

"It is important that the authorities fully invest in having an aggressive track, test and trace surveillance system to avoid costly additional lockdowns in the weeks and months ahead should the virus rebound," Kluge said.