Britvic’s Mathew Dunn has handed in his resignation and will be joining Asos as the new chief financial officer.

Dunn joined Britvic three years ago but will be moving onto the online retailer next spring, replacing Helen Ashton.

“I’m very much looking forward to working with the ASOS team. I’m motivated by their ambitious plans to realise the significant potential still ahead for the company,” Dunn said.

Nick Beighton, the Asos boss said: “I’m looking forward to working with Mathew. He brings us a totally relevant mix of operational experience together with a history of implementing and overseeing finance systems at an international level.”

Dunn’s resignation from Britvic comes after Ashton made a surprise departure from Asos.

On her resignation, Beighton said he would cover Ashton’s role until her replacement was identified.

Sales at the online fashion retailer have soared over the year.

Hargreaves Lansdown (LON: HL) analyst Laith Khalaf said earlier this year: “While clothing sales at M&S went backwards over the festive period, and Next was applauded by the market for eeking out 1.5% growth, ASOS is making retail look easy by turning over almost a third more sales than last year.”

“The online fashion retailer has proved very successful at attracting new customers, while at the same time increasing the amount existing customers are spending.”

“ASOS earns its crust from millennials, and has over 80 content producers tasked with showcasing its wares on social media, because it knows this is a key battleground for the attention of its young target audience,” he added.

Britvic (LON: BVIC) shares dropped 1.2% on Tuesday morning. ASOS (LON: ASC) shares also fell 1.6%.