President Donald Trump will not be unveiling former President Barack Obama’s portrait at the White House, a break in the 40-year tradition following a contentious exchange between the two over the weekend.

Trump and Obama perhaps have the most contentious relationship of any current and former presidents in modern US history dating back to Trump’s days in reality TV as he spent years perpetuating a racist conspiracy theory regarding Obama’s place of birth.

Though Obama did not mention Trump, the former president’s comments have been interpreted as taking a direct jab at his successor.

Similar ceremonies had occurred in the years before, such as when former first lady Jacqueline Kennedy returned to the White House in 1971 for the unveiling of the portraits of her and her husband, President John F. Kennedy.

The first formal portrait unveiling took place in 1978, when President Jimmy Carter invited his predecessor, President Gerald Ford, back to the White House for a ceremony in the East Room.