The UN's World Health Organization has raised the alert over the spread of swine flu to level five - one short of a full-blown pandemic.
A phase five alert means human-to-human transmission in at least two countries.
The move comes after a 23-month-old Mexican child died in Texas - the first death from swine flu outside Mexico, where the outbreak originated.
In Spain, officials confirmed the first case of swine flu in a person who has not travelled to Mexico.
Announcing the increased alert level, WHO Director General Margaret Chan urged all countries to activate their pandemic plans - including heightened surveillance and infection control measures.
She said action should be undertaken with "increased urgency".
A phase five alert means human-to-human transmission in at least two countries.
The move comes after a 23-month-old Mexican child died in Texas - the first death from swine flu outside Mexico, where the outbreak originated.
In Spain, officials confirmed the first case of swine flu in a person who has not travelled to Mexico.
Announcing the increased alert level, WHO Director General Margaret Chan urged all countries to activate their pandemic plans - including heightened surveillance and infection control measures.
She said action should be undertaken with "increased urgency".