The Zika virus outbreak should be considered a “public health emergency of international concern”, the World Health Organisation has said.
The global health body made its decision after an emergency meeting in Geneva to discuss the “explosive” nature of the virus.
WHO officials have predicted that as many as four million people could be infected with the virus this year.
The last time a global emergency was declared was for the Ebola outbreak, which is thought to have led to more than 11,000 deaths.
Zika has been linked to thousands of babies being born with underdeveloped brains in Brazil.
Colombia has also seen a rise in the number of patients diagnosed with a rare neurological disorder which can cause paralysis.