Donald Trump has issued his first official pardon as President, and his message is clear.

US President Donald Trump has pardoned former Arizona sheriff and political ally Joe Arpaio, less than a month after he was convicted of criminal contempt in a case involving his department’s racial profiling policy.

Trump had signaled this week that the first presidential pardon of his administration would go to Arpaio, aged 85, whom he has frequently praised for his hardline immigration stance.

“Throughout his time as sheriff, Arpaio continued his life’s work of protecting the public from the scourges of crime and illegal immigration,” said the White House statement announcing Arpaio’s pardon.

Arpaio, who lost a bid for re-election in Arizona’s Maricopa County in November after 24 years in office, was known for his crackdown on undocumented immigrants and investigating unfounded Trump-supported claims questioning former President Barack Obama’s citizenship.

Before Trump granted the pardon, the American Civil Liberties Union, which sought the court injunction against Arpaio, said it would be “a presidential endorsement of racism.”

It comes after the US president’s past criticism of federal judges, including the chief justice of the United States but supporters counter that the veteran law enforcement officer deserved America’s gratitude, “not the injustice of a political witch hunt”.

“I am pleased to inform you that I have just granted a full Pardon to 85-year-old American patriot Sheriff Joe Arpaio. He kept Arizona safe!,” Trump tweeted late on Friday after the White House announced that he had used his pardon power for the first time, sparing a political ally the prospect of jail time for defying court orders to halt police patrols that focused on Latinos.

Trump’s decision also followed the uproar that ensued after he said “both sides” were responsible for deadly violence during race-fuelled clashes this month in Charlottesville, Virginia.

Reaction to the decision was sharp and swift, including among some fellow Republicans.

House Speaker Paul Ryan signalled his disagreement with the pardon.

Listen to Mia Freedman and Amelia Lester discuss Trump on the most recent episode of Tell Me It’s Going To Be OK.

“Law-enforcement officials have a special responsibility to respect the rights of everyone in the United States,” he said in a statement. “We should not allow anyone to believe that responsibility is diminished by this pardon.”

Senator John McCain said: “The president has the authority to make this pardon, but doing so at this time undermines his claim for the respect of rule of law as Mr Arpaio has shown no remorse for his actions.”