A boom in Cadbury sales driven by the Olympics has helped former Kraft business Mondelez UK outperform its global owner, as its parent struggles to emerge from one of the biggest restructures in recent times.

Mondelez International last night reported weaker-than-expected sales for the second quarters in a row since it was formed by the split from Kraft Foods.

2012 net sales fell 2.2% in the year ending 31 December, to $35bn, with Q4 net sales down nearly 2%. Chairman Irene Rosenfield said they reflected a “transformational year”.

However, Mondelez UK revealed it had seen a strong performance across all its core sectors, three years since the controversial Cadbury takeover.

Value sales for Cadbury grew by 5.1% according to Nielsen figures for the same period and UK president Maurizio Brusadelli said London 2012 had helped the iconic brand flourish while non-core parts of the Kraft empire, notably its gum business, had struggled.

“We are at the centre of the company’s power brands strategy,” Brusadelli told The Grocer.

“The Olympics was something special and we were able to leverage it and we put a huge amount of marketing and NPD around it,” he said. “Three years on from the takeover it’s performing very strongly”

But he also said other parts of the UK business were thriving, with coffee sales up 12.3% in value over the same period according to Nielsen, including a 37% jump for its Carte Noire brand and a 27.2% year-on-year rise for its Tassimo partnership with Costa Coffee and Bosch.

There was also good news for its biscuits division, which saw value growth of 25.3%, including Belvita up 72% year-on-year.

“Its growth has been incredible,” said Brusadelli.

Mondelez described its European results as “solid” despite a fall in net sales of nearly 7% for 2012 and more than 7% in Q4.

“We successfully completed the spin-off of Kraft Foods Group, resulting in a significant increase in shareholder value and delivered solid- top line growth hand high adjusted operating income margins across all geographies,” said Rosenfield.

She added the business was “relentlessly focused” on leveraging the strength of its power brands, including Cadbury.