Apple said late Monday that it has rectified its after-sales policies in China concerning its iPhone 4 and iPhone 4S products, in a response to a torrent of media reports during the past two weeks accusing the American electronics giant of taking a double standard in its warranty policy.

According to an open letter to all Chinese customers posted on Apple's Chinese language website late Monday, the company stated that it has fixed the much criticized policies of its iPhone 4 and iPhone 4S products, and the new rules took effect Monday.

The letter is the third, as well as the most effective, in a series of statements issued since the American company became mired in its biggest public relations crisis in China.

Under the new rules, customers in China will have their devices replaced as a whole, after an exposé broadcast by China Central Television on March 15 said that when repairing phones, the old back covers are returned as a way of avoiding extending its warranty by another year.

In developed countries, customers are given a new phone as a replacement.

China's consumer regulation stipulates that warranties must be extended another year after repairs are made during the first year warranty.

"For those iPhone 4 and iPhone 4S devices that were sent to repair in February, the warranty would be automatically extended for another year," Apple China's public relations department told the Global Times in a reply late Monday.

In the letter, the company added it would post the exhaustive warranty policies online, strengthen supervision over authorized dealers and ensure that customers can reach the company to give their feedback through various channels.

The company also attributed the perception of arrogance and indifference to customers' feedback, as reported by many media outlets, to a lack of communication with customers, and apologized for all the misunderstandings it caused.

The apology came after the China Consumer Association demanded the company sincerely apologize to Chinese consumers.

Prior to Apple's letter, authorities of various government departments had taken Apple to task in a series of edicts and statements.

The General Administration of Quality Supervision, Inspection and Quarantine said Thursday Apple's after-sales service policies in China violate related regulations and must be rectified, after asking the company to extend its one-year warranty to two years to cover the main parts of its computer products.

However, the company clarified that it offers the two-year warranty to its laptop computers and iPad products.

The State Administration for Industry and Commerce also said that it has issued a notice asking local watchdogs to investigate and punish illegal acts concerning the company's warranty policies.

Related report: People’s Daily criticizes Apple for double-standard warranties