Delays hit launch of Samsung Galaxy S4 smartphone

The rollout of Samsung's latest flagship smartphone, the Galaxy S4, has been disrupted by supply problems, meaning it will go on sale at some carriers in the United States later than expected.

Samsung attributed the disruption to unexpectedly strong demand for the phone.

"Due to overwhelming global demand of Galaxy S4, the initial supply may be limited. We expect to fulfil inventory to meet demands in the coming weeks," a spokesman said.

The S4 is being introduced with much fanfare around the world. Earlier this week it was launched in Sydney, where the phone maker is sponsoring the Opera House. In the US, Samsung took out an eight-page insert in the Wall Street Journal to herald the device.

The South Korean company's latest challenge to Apple's iPhone is thinner and lighter than its predecessor.

It is still set to go on sale at UK carriers on Saturday as expected.