Former President Barack Obama recorded a phone message in recent days, telling Alabama voters to reject Republican Senate candidate Roy Moore in Tuesday’s special election.

“This one’s serious,” Obama says, according to CNN. “You can’t sit it out.”

Obama reportedly recorded the message as President Trump stepped up his own support of Moore, who has been accused by several women of sexual misconduct when they were in their teens and Moore was in his 30s.

Moore has denied all allegations.

Obama’s phone message is aimed at black voters, whose support is crucial for Democrat Doug Jones.

“Doug Jones is a fighter for equality, for progress,” Obama says. “Doug will be our champion for justice. So get out and vote, Alabama.”