The European Commission has extended until June 20 its deadline for Apple and major record companies to respond to its anti-trust concerns over iTunes pricing.

It comes two months after the Commission -- the European Union's anti-trust authority -- accused Apple and music giants Sony BMG Music Entertainment, Universal Music Group, Warner Music and EMI Group of possible violation of competition rules through the iTunes Music Store.

The original deadline was midnight on Monday, but it was extended after Apple and the record firms asked for more time, a spokesman for EU competition commissioner Neelie Kroes confirmed.

The Commission has already sent a "Statement of Objections" against alleged territorial restrictions in on-line music sales to Apple and the four majors.

The Statement is the Commission's charge sheet where it lists its initial concerns about potential market abuses, and the first step of formal antitrust proceedings.

The Commission says consumers can only buy music from the iTunes' online store in their country of residence -- thus restricting their choice of where to buy music, and consequently what music is available, and at what price.

European consumers are only able to download music from the iTunes site in their country of residence and prices differ from country to country within the 27-nation EU. Customers can only buy songs in the country where their credit card is registered.

Earlier this year, German and French consumer groups added their weight to a Scandinavian campaign to force Apple to make its iTunes online store compatible with digital music players that compete with the iPod. Songs bought and downloaded on iTunes work with iPods players but not rival models, like those using Microsoft Windows Media system. Nor can iPods usually play copy-protected music sold through non-Apple stores.