iPhone 7 Plus sold out before hitting stores

Apple has sold out of its highly coveted iPhone 7 Plus ahead of its release into stores on Friday.

Customers will not have access to the 5.5 inch models in stores, but can continue to purchase them online according to the technology giant.

The smaller version of the iPhone 7 will be available, except for the new jet black colour, which has also sold out.

"We sincerely appreciate our customers' patience as we work hard to get the new iPhone into the hands of everyone who wants one as quickly as possible," Apple spokeswoman Trudy Muller said in a statement.

The new phones, revealed earlier this month, feature improved cameras and have replaced the headphone jack with new technology.

The company has decided not to release its first-weekend sales of the new phone as the figure is more a reflection of supply than demand according to the firm.

The secrecy has sparked concerns among some on Wall Street as some predict the iPhone’s sales are calming down.

However, US-based wireless carriers Sprint Corp and T-Mobile US said on Tuesday that they received “strong” pre-orders for the iPhone 7, sending Apple shares up.

Analyst Jan from Jackdaw research seemed to agree. “Based on everything I've seen it looks like demand is very strong."