The World Health Organization says there is "no public health justification" for postponing or cancelling the Rio de Janeiro Olympics because of the Zika outbreak.
The assessment in a statement issued on Saturday follows an open letter to the UN health agency published by 150 health experts including former White House science adviser Dr Philip Rubin, calling for the games to be delayed or relocated "in the name of public health."
The letter cited recent scientific evidence the Zika virus causes severe birth defects, most notably babies born with abnormally small heads.
In adults, it can cause neurological problems, including a rare syndrome that can be fatal or result in temporary paralysis.
The authors also noted that despite increased efforts to wipe out the mosquitoes that spread Zika, infections in Rio have gone up rather than down.
Several public health academics have previously warned that having hundreds of thousands of people head to the August 5-21 games in Brazil will inevitably lead to the births of more brain-damaged babies and speed up the virus' global spread.
WHO said "based on current assessment, cancelling or changing the location of the 2016 Olympics will not significantly alter the international spread of Zika virus".
It noted Brazil is one of almost 60 countries and territories reporting transmission of the virus by mosquitoes.
Most people infected by Zika suffer only minor symptoms including fever, a rash and muscle or joint pain.
The UN agency has also previously predicted the Zika risk will drop in August since it will be the south American winter and there should be fewer mosquitoes.
