JK Shin, President and Head of IT and Mobile Communications for Samsung Electronics, presents the new Samsung Galaxy S 4 during the Samsung Unpacked event at Radio City Music Hall, Thursday, March 14, 2013 in New York. (Jason DeCrow/AP)

T-Mobile and Sprint will delay the launch of Samsung’s new Galaxy S 4 smartphone, due to shipment delays, the companies said.

The Galaxy S 4 is Samsung’s newest 5-inch flagship phone and its chief competitor to Apple’s iPhone. Samsung announced last month that it would begin selling the phone by the end of April in a flashy debut event.

T-Mobile was planning to take online orders for the phone starting Wednesday, but said that will now have to wait until April 29.

“We apologize for any inconvenience and are working with Samsung to deliver the device to T-Mobile customers as soon as possible,” the company said in a statement.

The much-anticipated device will cost T-Mobile users a $149.99 down payment with subsequent monthly payments of $2o for 24 months, in addition to the data plan of their choice.

Sprint also said that it will delay its full product launch for the much-anticipated phone, which had been slated for Saturday. The phone will be available online as planned, but will come to Sprint retail stores at a later date.

“Sprint is one of Samsung’s largest partners and we are working closely with them to launch in all Sprint channels as soon as possible,” the company said in a statement Wednesday.

Sprint is offering the 16GB model of the phone for $249.99 on contract. New Sprint customers who buy the phone will get an instant $100 credit on the device.

Not all carriers have delayed their launch dates.

AT&T confirmed that it will be able to offer the phone as planned, with the Galaxy S 4 arriving online and in stores on April 27. AT&T is offering the phone on contract; it will cost $199.99 for a 16 GB model and $299.99 for a 32 GB model.

Verizon, meanwhile, said that it will be taking pre-orders for the phone starting Thursday. It will be available sometime in May.

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