Amazon.com Inc. shares fell nearly 5% on Friday after the company warned its lucrative cloud services business slowed further in April, fueling concerns that the long-time growth driver was struggling with a pullback in technology spending.

The company, one of the largest in the world by market capitalization, is on track to shed about $60 billion from its valuation of $1.126 trillion, if losses hold.

Atlantic Equities analyst James Cordwell said the slowdown reflected Amazon Web Services' greater exposure to technology companies and start-ups, which have slashed spending in recent months in the face of rising interest rates and high inflation.

"This makes it more difficult to have confidence that Q2 will be the bottom in terms of the decline," Cordwell said.

Growth in the cloud business, whose steady cash flow has long funded Amazon's investments in other areas including online retail, had already slowed in the first quarter to the lowest rate since the company began breaking out the unit's sales.

However, finance chief Brian Olsavsky told a post-earnings call that growth in the business would fall by 5 percentage points this month from the 16% recorded in the first quarter as Amazon helps cloud clients lower their bills.

The results are in contrast to those of Microsoft Corp's Azure, which grew at 27%.

Synergy Research Group said Microsoft had increased its share of the cloud infrastructure market by a percentage point to 23% in the quarter, while market leader Amazon stayed within its long-standing share band of 32% to 34%.

Analysts were, however, largely upbeat about Amazon's cloud prospects, with about 17 raising their price targets on the stock, compared with the 10 that lowered their view.

CFRA Research analyst Arun Sundaram said the slowdown was largely a result of Amazon helping its clients move to lower-price tiers, and the company was not losing customers to other big players.

"Amazon is the clear market share leader in cloud computing and they will remain that way," Sundaram said.