The world has never been in a better position to end the COVID-19 pandemic, the head of the World Health Organization (WHO) said on Wednesday, his most optimistic outlook yet on the years-long health crisis which has killed over 6 million people. 

"We are not there yet. But the end is in sight," WHO Director-General Tedros Adhanom Ghebreyesus told reporters at a virtual press conference. 

That was the most upbeat assessment from the UN agency since it declared an international emergency in January 2020 and started describing COVID-19 as a pandemic three months later.

In its weekly report on the pandemic, the WHO said deaths fell by 22 percent in the past week, at just over 11,000 reported worldwide. There were 3.1 million new cases, a drop of 28 percent, continuing a weeks-long decline in the disease in every part of the world.

Still, the WHO warned that relaxed COVID-19 testing and surveillance in many countries means that many cases are going unnoticed. The agency issued a set of policy briefs for governments to strengthen their efforts against the coronavirus ahead of the expected winter surge of COVID-19, warning that new variants could yet undo the progress made to date.

"If we don't take this opportunity now, we run the risk of more variants, more deaths, more disruption, and more uncertainty," Tedros said.

Countries need to take a hard look at their policies and strengthen them for COVID-19 and future viruses, Tedros said. He also urged nations to vaccinate 100 percent of their high-risk groups and keep testing for the virus.

The WHO reported that the Omicron subvariant BA.5 continues to dominate globally and comprised nearly 90 percent of virus samples shared with the world's biggest public database. In recent weeks, regulatory authorities in Europe, the U.S. and elsewhere have cleared tweaked vaccines that target both the original coronavirus and later variants including BA.5. 

The WHO's next meeting of experts to decide whether the pandemic still represents a public health emergency of international concern is due in October, a WHO spokesperson said.

(With input from agencies)