On the streets of central Caracas thousands of Venezuelans marched, as they have also marched for the last month, protesting against President Nicolas Maduro.
They believe he is wrecking the economy and destroying civil liberties.
Security forces fired tear gas at youths throwing stones and petrol bombs.
Mr Maduro has called for the establishment of a new national assembly, but critics say it is an attempt to cling to power amid growing public frustration.
"Today I announce that through the use of my constitutional presidential powers as head of state, according to article 347, I invoke the original constitutional powers so that the working classes and the people, in a constituent popular process, convene a constituent national assembly."
In Cuba millions paraded through Havana's historic Revolution Square for traditional May Day celebrations.
It's the first since the death of Fidel Castro last year, and the last that his brother, Raul Castro, will attend as president.
In Turkey, police fired tear gas and rubber bullets to break up anti-government demonstrations in Istanbul, arresting 165 people.
And in South Africa, President Jacob Zuma made a hasty exit from a May Day rally he was due to address after workers booed him and fights broke out between his supporters and opponents.
The President has been under growing pressure since firing his widely respected finance minister a month ago.
France's traditional May 1st marches, staged by the country's powerful labour unions, erupted into violence.
Four police officers were injured in clashes in Paris as protesters threw petrol bombs at police who responded with teargas.
One officer was engulfed in flames and suffered serious burns.
It comes just days before France prepares to choose between Emmanuel Macron and Marine Le Pen as the country's next president.
Frontrunner Mr Macron told his supporters Ms Le Pen represents hatred and violence.
"The National Front party has not changed. It brings hatred, division -- and above all its a manifesto that would weaken the country, the purchasing power of our fellow citizens, workers, weaken industry and the economy because leaving Europe and the euro would weaken France."
But Ms Le Pen told her supporters Mr Macron is simply a clone of unpopular outgoing President, Francois Hollande.
"The reality is simple and clear: Emmanuel Macron is just Francois Hollande who wants to stick around, and is clinging onto power like a barnacle. Emmanuel Macron means it's Francois Hollande who will continue to run politics in this country. Well, this outgoing candidate - we're going to get him out!"
Share
