Hundreds of independent retailers are expected to take part in a day of action on July 11 to protest against Vodafone's 1% cut in retailers' margin for mobile phone top-ups.

In what is planned as the first of a campaign of protests, Lancashire retailer Kevin Hunt is calling on retailers to join him in a one-day boycott of Vodafone products.

Kevin said: “My margin is to be cut from 4.5% to 3.5% from August 1, with no explanation. It's quite astonishing - it feels like we're being bullied. If we stand together we can send a message to the Vodafone board that this is unacceptable and we won't allow it.”

Retailers can register their support at a website, . “I'm expecting at least 750 stores to join the protest on Friday,” Kevin added. “We have to protect our livelihoods, and be prepared to take even more drastic action.”

A Vodafone spokesperson said: “This decision has not been taken quickly or lightly. We are investing to attract and retain customers and stimulate more use of our products and this rate cut is part of that strategy. We believe this investment will boost top up sales and bring more people into convenience stores.”

Retailers fear that electronic payment terminals will not be profitable if the top up rate is cut and have called on service providers including PayPoint and Payzone to join them in condemning Vodafone's decision.

A Paypoint spokesperson said: “We fully understand the impact that this announcement will have on our retail agents. Whilst Vodafone is entitled to review rates, we are continuing to represent our agents’ interests as robustly as possible”.

Payzone managing director Paul Charmatz said the company understood the strength of feeling against the rate cut. “We’ve consulted at length with Vodafone to help them to understand this strength of feeling,” he added.