More than 6,000 cases of monkeypox have now been reported from 58 countries in the current outbreak, according to the World Health Organization.

The U.N. agency will reconvene a meeting of the committee that will advise on declaring the outbreak a global health emergency, the WHO's highest level of alert, in the week beginning July 18 or sooner, Director-General Tedros Adhanom Ghebreyesus told a virtual news conference from Geneva.

At its previous meeting on June 27, the committee decided that the outbreak, which has seen cases rising both in the African countries where it usually spreads and globally, was not yet a health emergency.

"I continue to be concerned by the scale and spread of the virus across the world," Tedros said, adding that a lack of testing meant that there were likely many more cases going unreported.

Around 80% of cases are in Europe, he said.

Monkeypox, a usually mild viral infection that causes flu-like symptoms and skin lesions, has been spreading worldwide since early May. The fatality rate in previous outbreaks of the strain currently spreading has been around 1%.