The new agency is being headed by the co-founder of StrawberryFrog Brian Elliott. It will operate out of StrawberryFrog's former Amsterdam premises, staffed by the same people. However, StrawberryFrog and Amsterdam Worldwide have legally severed all ties.
Campaign announced last week that Scott Goodson, who founded StrawberryFrog in 1999 with Elliott, is instead planning to launch a StrawberryFrog-branded agency in London. It will no longer have an Amsterdam operation.
StrawberryFrog London is in the process of hiring a senior management team.
Sources close to Elliott and Goodson say they fell out last year over expansion plans, with Goodson regarding London as the best hub for Europe and the former believing the lead business should remain in Amsterdam.
Elliott said: "It's a question of moving on. The focus is on what we do, rather than what we say we do."