Premiership-winning rugby league coach Warren Ryan is to be charged after he allegedly assaulted another man in an argument over Donald Trump at a pub in Sydney's east.

NSW Police said Ryan, 75, will be charged with assault occasioning actual bodily harm over the incident at the Pagewood Hotel at Maroubra on November 11.

Former first grade coach Warren Ryan has been charged with assault Credit:Sahlan Hayes

Ryan became involved in a heated altercation with another man, also 75, when he allegedly turned violent and assaulted the other man.

It is understood the initial argument was about the US presidential election and Donald Trump's victory just days earlier.