Amazon says coronavirus is hampering its ability to meet some customers' needs.

The e-commerce giant said in a blog post Saturday that there has been a surge in online shopping as the coronavirus outbreak spreads — and it's weighing on the company. The number of cases in the United States surpassed 3,000 on Sunday.

Amazon, which has made speeding up shipments a key part of its business strategy over the past year, said customers may experience more extended delivery times than usual because of the high volume of orders.

The company also said it is out of stock on "some popular brands and items, especially in household staples categories." A search by CNN Business Saturday night showed that among the things Amazon appears to be out of are brand-name toilet paper and several types of brand-name disinfectant wipes.

"We believe our role serving customers and the community during this time is a critical one, and we want to make sure people can get the items they need, when they need them," the company said in the post Saturday. "We are working around the clock with our selling partners to ensure availability on all of our products, and bring on additional capacity to deliver all of your orders."

Amazon has also had to grapple with sellers on its site trying to capitalize on the outbreak inappropriately.

Earlier this month, Amazon said it pulled more than 1 million products for price gouging or falsely advertising effectiveness against the coronavirus.

“We actively monitor our store and remove offers that violate our policy,” the company said in its blog post this weekend.