Senator Jeff Sessions
Senator Jeff Sessions Reuters

Senator Jeff Sessions (R-AL) on Sunday endorsed Republican candidate Donald Trump for president, becoming the first senator to endorse the first-time candidate and billionaire businessman, Fox News reported.

The Alabama Republican endorsed Trump at a campaign rally in Mobile.

"The American people are not happy with their government. So some say we should forget it, there is an opportunity this year, Tuesday, the last opportunity we have for the people's voice to be heard. Has the government fixed immigration? Donald Trump will do it," Sessions said, according to Fox News.

"I am pleased to endorse Donald Trump for the presidency of the United States,” he added.

The network noted that endorsement is not a total surprise, considering Sessions has appeared on stage before at a Trump rally. However, it will likely be considered a setback for fellow GOP presidential candidate Texas Senator Ted Cruz, whom Sessions has supported.

The backing from Sessions came two days after New Jersey Governor Chris Christie offered a surprise endorsement to Trump, saying there is no one better prepared to lead the country or defeat former Secretary of State Hillary Clinton should she become the Democratic nominee.

Christie's endorsement came days after he suspended his own presidential bid.

Trump has also been endorsed by a number of controversial public figures, including leading American White Supremacist David Duke - a former leader of the Ku Klux Klan – and Jean-Marie Le Pen, who founded the far-right National Front party in France.