Auction site eBay has pulled its advertisements off the Google search engine in the US.

The move is believed to be retaliation against a protest party that Google intended to stage at the eBay Live conference in Boston later this week.

Google's 'Let Freedom Ring' party has since been cancelled, but was scheduled to take be held in the Old South Meeting House in Boston, which was a key meeting place for participants during the early days of the American Revolution.

The Google party would have highlighted Google Checkout, a payment technology that the search company introduced in June 2006. The service competes with eBay's Paypal.

EBay prohibits sellers from using the Google service, officially because it lacks a safety track record. But Google has claimed that there is no need for a ban now that Google Checkout has been adopted by more than 500 online retailers.

EBay did not immediately return a request for comment.

The auction firm has stated officially that the advertising move was the result of a regular reallocation of its marketing budgets. The company has acknowledged, however, that the event ruffled the features of some high level executives.