Imagination Technologies said no progress has been made following its well-publicised spat with Apple, and that its options on the matter are “being reviewed”.

Earlier this year, the iPhone maker – which is Imagination’s biggest customer – told the graphics technology player it would stop using its intellectual property in the not-too-distant future. This would mean it no longer needed to pay royalties.

Imagination said it would be “extremely challenging” for Apple to design a new graphics processing unit without infringing its intellectual property rights. It noted that the US company had not presented any evidence to back-up its claims.

“Apple’s unsubstantiated assertions and the resultant dispute have forced us to change our course, despite the clear progress we have been making,” said chief executive Andrew Heath.

While Imagination initially said it would sell two of its businesses to strengthen its balance sheet and enable it to focus its resources, it subsequently received offers for the business as a whole.

With regard to the sale of the units, it said “the progress is going well”; as for selling as a whole, preliminary talks continue with potential bidders.

The company made the comments in line with its results announcement for the year to 30 April 2017.

It announced a loss for the year of £27.91 million, compared with a prior-year loss of £80.86 million, on continuing revenue of £145.21 million, compared with £121.55 million. The company’s operating profit from continuing operations improved to £7.8 million from a loss of £26.8 million.