Bernard resigned from Initiative in December to take a senior management role at Grand Vision, which owns Vision Express in the UK. However, he has subsequently resigned following changes in strategy.
He now aims to launch a full-service agency in the autumn, with the support of senior media and creative figures in different markets. The business, which will not be backed by an advertising holding company, is expected to launch in the UK, France, Spain and Belgium.
Bernard said: "Media will be at the centre of our creative offer. This is something ad agencies have given up and it is a major mistake."
Bernard, who declined to provide details of clients or senior hirings, has spent most of his career on the creative side. He was president of Lowe France before becoming the European president of Lowe.