Former Republican presidential candidate Marco Rubio on Monday rejected the possibility that he would serve as Donald Trump’s running mate.

“While Republican voters have chosen Donald Trump as the presumptive GOP nominee, my previously stated reservations about his campaign and concerns with many of his policies remain unchanged,” the Florida senator who dropped out of the race after losing to Trump in his own state told CNN in a statement.

“He will be best served by a running mate and by surrogates who fully embrace his campaign. As such, I have never sought, will not seek and do not want to be considered for Vice President,” added Rubio.

“Instead,” he continued, “I will focus my attention on representing the people of Florida, retaining a conservative majority in the Senate and electing principled conservatives across the country.”

Rubio was last month rumored to be a potential vice presidential candidate for Ted Cruz, but Cruz himself also dropped out of the race last week, following a loss to Trump in Indiana.

That Rubio would rule himself out as a potential vice presidential pick perhaps isn’t much of a surprise, noted CNN, given how acrimonious things got between Trump and the Florida senator earlier this year.

Rubio ratcheted up his attacks in February, calling Trump a “con artist.”

After bowing out the presidential race in March, Rubio returned to the Senate and said he didn’t want to be on any candidate’s ticket.

“I’m not going to be anybody’s vice president,” he said at the time.