The great London 2012 Olympic chip embargo has cracked. No longer will hungry workers at the games be denied pie and chips, chicken and chips or even just chips because of a monopoly enforced by McDonald's, a major sponsor.

On Wednesday, the London Organising Committee responded to plaintive cries of caterers who had grown tired of receiving "grief" from chip-hungry staff working on the opening and closing ceremonies and allowed chips to be served outside branches of the fast food chain McDonald's.

It all results from one of the stranger twists of Olympic planning. McDonald's sponsorship deal included the exclusive right to sell chips in and around Olympic venues. Other caterers had negotiated special rights to serve chips with fish – but not chips on their own, or with anything else.

Cue frustrated scenes at the lunch counter in the ceremonies catering area where staff were toiling over the staging for Danny Boyle's 27 July opening extravaganza. "Please understand this is not the decision of the staff who are serving up your meals who, given the choice, would gladly give it to you, however they are not allowed to," read a notice pinned up by staff. "Please do not give the staff grief, this will only lead to us removing fish and chips completely."

"It's sorted," said a spokesman for Locog. "We have spoken to McDonald's about it."

But the embargo will hold in other areas. That means no chips with anything other than fish anywhere else in the park unless spectators dine at McDonald's.

On Wednesday catering staff in the media centre were taking no risks. There were hash browns and dauphinoise, but no chips. A server explained why: "Because McDonald's own the rights, so we're not allowed to".