In a notice on Apple's Chinese homepage , chief executive Tim Cook admitted that a lack of external communication had led to a perception that Apple was “arrogant” and did not value consumer feedback. He made “sincere apologies” for what he called “misunderstandings” and stressed Apple's “immense respect” for China.

The Chinese media attacks began in mid-March, when a flagship news show on China Central Television accused Apple of discriminating against Chinese customers with its after-sales service.

Complaints by celebrities and other prominent bloggers accompanied the broadcast. The apparently co-ordinated campaign prompted derision of CCTV by some internet users in China, who questioned the broadcaster's motives.

At the time, Apple denied that its warranties and customer service in China were any different than in other countries. Yet Chinese state media outlets persisted with prominent coverage lambasting Apple for being “greedy” and “incomparably arrogant”。 Apple's executives were also criticised for not granting interviews.

A recurring point of complaint was Apple's use of “refurbished” parts for repairs – a common practice in its global maintenance programmes.

China's quality inspection bureau said last week that Apple would face “severe repercussions” if it did not improve its warranties, while the Chinese Consumers' Association demanded an apology from the company. In one concession, Apple extended the warranty of any iPhone 4 or 4S repaired in the last year, something it does not offer elsewhere.

Mr Cook also said in Monday's letter that Apple had improved its repair policies and training for its service providers in the country and would make it easier for customers to provide feedback. “We recognise that some people may have viewed our lack of communication as arrogant, or as a sign that we didn't care about or value their feedback,” he wrote. “We sincerely apologise to our customers for any concern or confusion we may have caused.”

The webpage sets out in detail Apple's warranty and maintenance policies for all of its products. It said that nearly 90 per cent of affected customers were satisfied with their repairs.