Prices begin at £849 including VAT and the new models are available to order today, with stocks arriving in Apple Stores tomorrow, the company said.
"Portable, affordable and powerful, MacBook Air is the ultimate everyday notebook," said Philip Schiller, Apple's senior vice president of Worldwide Product Marketing.
"MacBook Air features our most advanced technology and is an ideal match for Lion, especially with its new Multi-Touch gestures, full-screen apps, Mission Control and Mac App Store."
According to Apple, the new MacBook Airs are up to twice as fast as the previous generation of MacBook Airs. The backlit keyboard, present in the original MacBook Air but missing from the second generation has returned.
Thunderbolt ports are also present in the new MacBook Air range, bringing them up to speed with the MacBook Pro and iMac product lines. The new MacBook Airs all sport Intel's Sandy Bridge processors, which promise increased performance and better power efficiency. All of them also come with Mac OS X 10.7 Lion installed.
The 1.6 GHz 11in MacBook Air is available in two models, one with 2GB of memory and 64GB of flash storage for a suggested retail price of £849 inc VAT, and one with 4GB of memory and 128GB of flash storage for £999 inc VAT.
The 1.7 GHz 13in MacBook Air comes in two configurations, one with 4GB of memory and 128GB of flash storage for a suggested retail price of £1,099 inc VAT, and one with 4GB of memory and 256GB of flash storage for £1349 inc VAT.
Configure-to-order options and accessories include a 1.8 GHz Core i7 processor, additional flash storage, MacBook Air SuperDrive and a USB Ethernet Adapter.