Wyatt takes on the UK director of corporate affairs post alongside his European role, in the wake of White's departure.
White, who was unavailable for comment as PRWeek went to press, resigned from the top UK PR post late last month - a role he had held since 1998, when Price Waterhouse and Coopers & Lybrand merged.
Prior to the merger, White was UK head of PR for Coopers & Lybrand, while Wyatt was director of marketing and communications for the then Price Waterhouse.
White has not yet announced his next career move, but Wyatt said: 'Roger decided to move on and do other things.'
PwC - the world's largest professional services firm - denied the merger of the UK and European role was a cost-cutting move.
'It made sense to combine two roles and ensure messages are consistent across the UK and Europe,' said Wyatt.
Wyatt takes on responsibility for all PR, the press office, internal communications and government relations.
'The UK is the second largest market next to the US for PwC,' he said.
'It's a critical time for the profession, as it is subject to a lot of scrutiny,' he added.
In the UK role, Wyatt reports to UK management board partner Patrick Figgis.