The BBC was yesterday forced to axe commercial sponsorship from its external events including Sports Personality of the Year and Proms in the Park, after furious complaints from ITV and commercial radio rivals were upheld.

The BBC Trust ruled the corporation's management had "compromised the editorial integrity of the BBC" with an agreement for Britvic juice brand Robinsons to sponsor the Sports Personality of the Year award last December.

In light of the decision, the BBC said it would abandon all its commercial deals once existing agreements ran out, and axe a controversial website that had outlined sponsorship opportunities. The move will cost the BBC around £1.5m a year.

"In the context of today's findings, the management of the BBC ... has concluded that it should no longer accept sponsorship from commercial bodies for any on-air BBC event," it said.

The ruling will affect Sports Personality of the Year, sponsored by Robinsons; Proms in the Park, sponsored by National Savings & Investments; Radio 3's New Generation Artists Scheme, sponsored by Aviva; and BBC 4 World Cinema, which does not have a commercial partner but was previously sponsored by Pioneer.

The BBC had argued that the two-year Sports Personality sponsorship deal, worth an estimated £200,000, complied with editorial guidelines because the money funded the live event, expanded the year before to accommodate 9,000 members of the public, rather than the programme itself. But the trust said that the BBC had broken its guidelines, which it said were not sufficiently robust. It ordered the director general, Mark Thompson, to apologise in writing to ITV and commercial radio trade body RadioCentre.

The ruling was welcomed by RadioCentre and ITV. The Liberal Democrat culture, media and sport spokesman, Don Foster, said it was "a welcome reminder to the BBC about where the limits to its commercial activities should lie". The Consrvative shadow culture secretary, Jeremy Hunt, said: "This is a slap in the face for the BBC, and rightly so."