The US economy grew by an annual rate of just 0.2% in the three months to the end of March, official figures show.
The growth figure was far lower than expectations. Analysts had forecast growth would be about 1%.
Harsh winter weather for a second year dampened consumer spending, while energy companies struggling with low oil prices slashed spending.
A strike by dock workers at normally busy West Coast ports also hindered growth, the government said.
But the US Commerce Department said there were signs that activity was picking up in the second quarter.