Apple has finally confirmed its much-anticipated media event next week, dropping its biggest hint yet that it is poised to unveil the new version of the iPhone.

The firm issued invitations yesterday for an event that will take place at its California HQ on 12 September, a date that has been pencilled in for some months. The invite consists of merely two numbers, a '12' (to signify the date) and a dropped shadow '5' hinting at the new iPhone’s likely model number. It is thought that the new device could begin shipping nine days later on 21 September.

Speculation about a newly-designed version of the iconic device has been building for months. A new-look iPhone would be the first redesign since the iPhone 4 launch in 2010 – last year’s iPhone 4S upgraded many components but retained the same design.

It is thought that the new model will be thinner and will feature a larger screen – possibly up from 3.5-inches to as much as 4.2-inches – and will sit in a new brushed aluminium casing. Even the iconic white earphones are understood to have been redesigned for the first time in the iPhone’s lifetime.

The long-standing 30-pin connector used on all Apple gadgets since the iPod is said to have been replaced with a nine-pin version, which could make the ‘iPhone 5’ incompatible with older equipment.

Sales of the current iPhone have tailed off in the last few quarters as consumers wait for the anticipated new model. Apple sold 26 million iPhones in its last fiscal quarter, up from 20.3 million a year ago but down from 35.1 million the previous quarter.

According to figures from IDC this week, Apple shipped 5.2 million iPhones in Western Europe in Q2, representing a 19 percent share of the region’s smartphone market. That was up from 4.6 million a year earlier but was way behind smartphone market leader Samsung, which shifted 11. 9 million units (a 43.6 percent share) in Western Europe during the period.