Nokia has been forced to apologise after it was noticed footage shot to promote its PureView camera was faked.

The Finnish phone company unveiled the footage while announcing its new Lumia 920 and 820 smartphones in New York on Wednesday.

It was intended to show off the new optical image stabilisation feature, and was seemingly presented as if it was shot with a Lumia 920.

The clip showed a young man and women riding bikes on a waterfront. But a reflection seen in a window showed that the footage was not shot with a Lumia, but a large camera set up in a white van, with a lighting rig.

The mistake was spotted by gadget sites after the announcement, and Nokia eventually offered an apology.

READ MORE: Nokia Unveils New Lumia Devices

It said: "In an effort to demonstrate the benefits of optical image stabilization (which eliminates blurry images and improves pictures shot in low light conditions), we produced a video that simulates what we will be able to deliver with OIS.

"Of course, hindsight is 20/20, but we should have posted a disclaimer stating this was a representation of OIS only. This was not shot with a Lumia 920. At least, not yet. We apologize for the confusion we created.

"We are looking forward to bringing the Lumia 920, with PureView optical image stabilization to select markets later this year."

The company also posted a video which it said demonstrated the real difference between its new camera and existing technology.