Apple has reached an out-of-court settlement with a group of US states who had accused it of conspiring with publishers to fix the prices of e-books.

Eleven months after the US Justice Department found Apple guilty of violating competition laws in its effort to push into the e-books business, it reached a deal to settle the states' class-action suit.

The suit had sought up to $840m in actual and punitive damages, according to court documents. 

The details of the settlement were not divulged, and it still must be approved by a judge. 

In addition, the settlement must await the decision on Apple's appeal in the original competition case. 

In the case with the states, Apple was accused of overcharging book buyers a total of $280m, and the plaintiffs sought three times that much to punish the company.

The states' complaint, filed on behalf of consumers, accused Apple of working with five top publishers in 2009-2010 to set the prices of electronic books in an Apple-led effort to break into rival Amazon's dominance of the market. 

Their complaint was filed on the heels of last July's federal court verdict against the iPhone and iPad maker, finding Apple guilty of conspiracy to fix prices of e-books with the publishers. 

But the California-based tech giant was not fined in that case - instead, it was forced to agree to not enter any special deals with publishers, and to retain a compliance monitor to prevent the company from engaging in any competition activities.