A wild card is set to be thrown into the battle by Kraft to acquire UK confectionery group Cadbury with the expiry on Friday of an agreement by shareholder Nelson Peltz to refrain from publicly criticising the US food group.

Mr Peltz’s Trian fund management company – which holds stakes in Kraft and Cadbury – had struck a two-year “standstill” agreement with the US group in November 2007 not to criticise its “corporate strategy, business, corporate activities or management”.