A spokesman for George W. Bush says the former US President does "not plan to participate in or comment on" the 2016 presidential race.
The spokesman, Freddy Ford, was responding to an inquiry from AP about whether Bush planned to support Donald Trump now that the businessman is the presumptive Republican nominee.
While Bush has largely stayed out of politics since leaving the White House, his refusal to publicly support his party's nominee is remarkable.
It underscores the deep frustration within some corners of the GOP over Trump's candidacy.
The former President helped raise money for his brother Jeb Bush's failed primary campaign.
He also headlined a rally for his brother in South Carolina where he implicitly criticised Trump for inflaming Americans' anger and frustration.