The WHO's Western Pacific division held a media briefing this week to discuss the coronavirus.
Asked when regional countries might lift some restrictions imposed under their states of emergency, the WHO Regional Director Takeshi Kasai urged caution.
"When we consider lifting, we need a careful analysis of the situation And we should not lift everything all at once."
Dr Kasai said this applied to all countries, including those in the Pacific islands who had no reported cases of Covid-19.
All Pacific Islanders had a part to play in protecting their countries during the pandemic, Mr Kasai said.
Dr Kasai responded to a question from Tongan media about when was safe to return to "normal life" at school, churches, in social groups and sporting events.
"I know it's very difficult, life under social distancing or the movement control. But very important that every individual play their part," he said.
"There are ways to protect yourself, and ways to protect your family and community in general."