Apple said Tuesday it will begin selling its latest iPhones in China from October 17 after the Chinese regulator pressed the US giant to improve personal data security to gain approval.

Apple launched the large-screen iPhone 6 and iPhone 6 Plus in 10 countries and regions on September 19, though not in mainland China, with state media saying problems with licensing were the main obstacle.

The absence of China in the first round of sales was notable because Apple launched the iPhone 5s and 5c in the mainland at the same time as other major markets last year.

But on Tuesday the Ministry of Industry and Information Technology said on its website it had granted a network access licence for the phone.

The ministry said that in order to approve the licence it had sought pledges from the company to address concerns over the phone's iOS operating system, owing to fears it risked leaking personal information.

Third parties could obtain information stored on an iPhone by accessing a "trusted" computer or from an iPhone undergoing repair, the statement said.

"The ministry discussed the issue with Apple and raised related requirements on security management," it said.

Apple pledged to upgrade security and protect privacy and "promised it 'never established any so-called backdoor with any government organisations of any countries regarding any product or service' and 'never will'", according to the statement.

Chinese state broadcaster CCTV in July accused Apple of threatening national security through the iPhone's ability to track a user's location. Apple has denied any such threat.

Apple chief executive officer Tim Cook welcomed news of the approval.

"We are thrilled to bring iPhone 6 and iPhone 6 Plus to our customers in China on all three carriers at launch," he said in a news release, referring to China Mobile, China Telecom and China Unicom.

The world's second-largest economy is a key market for the US company, whose products enjoy a devoted following.

- Black market prices falling -

Apple's revenue in Greater China -- which includes Hong Kong and Taiwan -- is second only to the United States, and Cook has said he expects it to become the company's biggest market in time.

Fans of the iPhone in China cheered the announcement on social media. "Every organ of my body is so happy that they want to sing!" gushed Miquelito on Sina Weibo, China's version of Twitter.

Apple on Tuesday announced a suggested retail price in China of 5,288 yuan ($867) for the cheapest iPhone 6 with 16GB of storage, while the iPhone 6 Plus starts at 6,088 yuan ($998).

The first day of global sales for the phones was a huge success, with Apple breaking its sales record for an opening weekend of a new iPhone model, delivering 10 million in three days and boasting it could have sold more if it had them.

There were reports of Chinese buyers snapping up iPhones from Tokyo to the United States, leading to speculation of smuggling into the mainland on a massive scale.

In the commercial hub Shanghai, customs seized 453 iPhone 6 and iPhone 6 Plus models within ten days after the launch.

On Tuesday black market dealers in Beijing were quoting prices of 6,250 yuan to 8,000 yuan for an iPhone 6 with 16GB, but said prices had already come down.

"The prices were much higher days ago, I assume they will be lower after the holiday," one told AFP. China's week-long National Day holiday, which begins Wednesday, is traditionally a peak period for shopping.

Analysts forecast solid sales for Apple with the official launch.

"It should sell better than its previous products, as it's a big-screen mobile phone launched to meet users' needs," said Wang Jun of consultancy Analysys International.

"It's expected to achieve a big breakthrough (in sales) compared with previous models," he told AFP.

Apple held only a 6.9 percent share of China's fractured smartphone market in the second quarter of this year, according to Analysys, putting it in sixth place.

Rival Samsung of South Korea commanded the top position with a 15.4 percent share of the market, which has many cheaper offerings using the rival Android operating system.