The head of the World Health Organization on Monday called the COVID-19 vaccine crisis "scandalous" and warned the world remains in a dangerous situation.

In his opening remarks to the 74th World Health Assembly, WHO Director-General Tedros Adhanom Ghebreyesus said more cases have been reported so far this year than in 2020 and if the trend continues, the number of deaths from COVID-19 will overtake last year's total within the next three weeks.

"No country should assume it is out of the woods, no matter its vaccination rate," he said, adding though that no variants have so far emerged that significantly undermine the efficacy of vaccines, diagnostics or therapeutics. "But there is no guarantee that will remain the case".

Tedros lashed out at the vaccine inequality in the world, saying, "the ongoing vaccine crisis is a scandalous inequity that is perpetuating the pandemic".

WHO said more than 75 percent of all vaccines have been administered in just 10 countries.

"There is no diplomatic way to say it. A small group of countries that make and buy the majority of the world's vaccines control the fate of the rest of the world," he said.

The number of doses administered globally so far would have been enough to cover all health workers and older people if they had been distributed equitably, Tedros said.

"We could have been in a much better situation," he said.

The WHO chief said countries that vaccinate children and other low-risk groups now do so at the expense of health workers and high-risk groups in other countries. He said the number of doses for COVAX, the global initiate for equitable vaccine distribution, remains "vastly inadequate".

Tedros called on member states to support a massive push to vaccinate at least 10 percent of the population of every country by September and achieve another goal of vaccinating at least 30 percent by the end of 2021.

UN Secretary-General Antonio Guterres also warned of the dangers of a two-speed global response.

"We are at war with virus. We need the logic and urgency of a war economy, to boost the capacity of our weapons," Guterres said.

South African President Cyril Ramaphosa also called for correcting the huge global divide in vaccination rates. "This is not only a moral imperative. Effective and comprehensive global vaccination is vital to ending the pandemic," he said.