Amazon.com forecast second-quarter revenue largely above estimates Thursday, in a reassuring sign the e-commerce giant would navigate tariff-related uncertainty, but growth in its closely watched cloud unit lagged.

Shares of the company fell 5% in after-hours trading.

Amazon Web Services, the company's cloud unit, is showing signs of weakness, with revenue growth of 17% to $29.27 billion missing expectations of a 17.4% growth.

AWS, the largest cloud provider, lagged No. 2 player Microsoft, which reported blowout cloud numbers on Wednesday, as well as Google Cloud which reported revenue just shy of Wall Street expectations.

Amazon reported total revenue of $155.7 billion for the first quarter ended March 31, compared with analysts' estimate of $155.04 billion, according to data compiled by LSEG.

The company expects net sales between $159.0 billion and $164.0 billion for the second quarter, compared with analysts' average estimate of $160.91 billion, according to data compiled by LSEG.