The US president called the figure of 3,000 deaths a move by Democrats to make him look bad.
Thousands of people died when Hurricane Maria hit Puerto Rico.
Researchers revealed that the original death toll of 64 was severely undercounted.
Donald Trump has given himself a "10 out of 10" for the response to the widespread hurricane devastation Puerto Rico suffered.
US President Donald Trump has joked Puerto Rico's damage from Hurricane Maria has put his budget "out of whack".
Thousands of people downstream of a dam have been evacuated, but authorities are unable to reach many on the hurricane-hit island.
Footage shows the dangerous rescue effort after the family were left at the mercy of the sea on a boat overturned by Hurricane Maria.
More than 15 people are dead and 20 remain missing after Hurricane Maria's direct hit on Dominica, the prime minister has said.
A disaster has been declared in Puerto Rico after Hurricane Maria slammed the US territory.
In the wake of Hurricane Irma, the Category 5 storm is set to bring more devastation.