New York -- Amazon on Wednesday reported strong increases in profits and net sales during its fiscal first quarter, helped by surging growth in its prominent cloud computing unit.

The e-commerce and technology company said that sales in its cloud computing unit were up 28% in the January-March period, the fastest increase in 15 quarters. Amazon Web Services had 24% sales growth in the fourth quarter, which followed the division's 20% growth in the third quarter.

The Seattle-based company also offered a bullish outlook for net sales in the current quarter, surpassing analysts' estimates. However, shares slid nearly 2% in after-hours trading before rising about 3%.

Investors were closely watching Amazon’s quarterly earnings to see if the company’s $200 billion investment in artificial intelligence, robots, semiconductors and satellites is starting to pay off. The planned expenditure for the year marked a 60% increase from Amazon’s $128 billion in capital spending last year and spooked investors, sending the stock down 11% in after-hours trading when it was announced in February.

CEO Andy Jassy defended the spending during the previous quarterly earnings call, saying Amazon expected long-term returns on its invested capital.

The results from the latest quarter underscored that demand keeps growing for Amazon's services and technology.

“We’re in the middle of some of the biggest inflections of our lifetime, we’re well positioned to lead, and I’m very optimistic about what’s ahead for our customers and Amazon,” Jassy said in a release Wednesday.

Amazon came out with its first-quarter earnings the same day as three other tech giants — Microsoft, Meta and Alphabet — were reporting theirs, giving investors a read on AI spending and cloud growth across the industry.

Big deals that Amazon signed with OpenAI, Anthropic and Meta this month gave the company solid momentum.

Amazon announced what it called a “major expansion” of its partnership with ChatGPT maker OpenAI on Tuesday, a day after the artificial intelligence company said it was loosening its ties to longtime backer Microsoft.

Last week, Anthropic agreed to commit more than $100 billion to Amazon’s AWS cloud platform over the next 10 years to train and run the artificial intelligence company’s Claude chatbot. The partnership will allow Anthropic to secure up to 5 gigawatts of Amazon’s Trainium chips to train and power their artificial intelligence models, Amazon said.

Also last week, Amazon said that Meta, which owns Instagram, WhatsApp and Facebook, signed an agreement to power agentic AI on AWS’ Graviton chips.

Like other retailers, however, Amazon is experiencing higher tariff costs because of President Donald Trump’s foreign trade policies. Rising shipping costs as the Iran war affects oil and fuel prices also could cut into the company's e-commerce revenue.

Amazon this month said it would impose a 3.5% fuel and logistics surcharge on some third-party sellers using its platform. The temporary charge was effective April 17 for many of the sellers that use Amazon’s fulfillment services, the company confirmed to The Associated Press.

Meanwhile, Amazon has been speeding up order delivery times through a combination of robotics, AI technology and more efficient warehousing. In fact, speedier delivery helped Amazon dethrone Walmart in February from its status as the nation’s largest company by revenue, according to Fortune, which compiles a ranking of the top 500 U.S. corporations by total revenue for their respective fiscal years.

A new ultra-fast service called Amazon Now offers deliveries of orders from a selection of thousands of items in 30 minutes or less. The service is now available in various cities in India, Mexico and the United Arab Emirates and is being tested in several communities in the U.S. and the United Kingdom, the company said in February.

The company said on Wednesday that the service has expanded to parts of Tokyo and eight major cities in Brazil, bringing the total availability of Amazon Now to tens of millions of customers across nine countries. It plans to continue expanding the service in the U.S. and around the world this year, Amazon noted.

Amazon reported earnings of $30.3 billion, or $2.78 per share, for the three-month period ended March 31. That compared with $17.1 billion, or $1.59 per share, in the year-ago period.

Net sales rose 17% to $181.5 billion in the quarter, compared with $155.7 billion in the year-ago quarter.

Analysts were expecting $1.63 per share on sales of $177.28 billion, according to analysts surveyed by FactSet.

Revenue from Amazon Web Services reached $37.58 billion. Analysts were expecting $36.6 billion, according to FactSet.

For the current quarter, Amazon said it expected net sales will be in the range of $194 billion to $199 billion.

That would mean an increase of between 16% to 19% from the year-ago quarter. Analysts were expecting $188.96 billion in the current period, according to FactSet.