(CNN) Former Massachusetts Gov. Bill Weld announced Monday he is officially entering the race for president, becoming the first Republican to challenge President Donald Trump in the 2020 race.

"Ours is a nation built on courage, resilience, and independence. In these times of great political strife, when both major parties are entrenched in their 'win at all cost' battles, the voices of the American people are being ignored and our nation is suffering," Weld, who had previously formed an exploratory committee , said in a statement.

"It is time for patriotic men and women across our great nation to stand and plant a flag. It is time to return to the principles of Lincoln -- equality, dignity, and opportunity for all. There is no greater cause on earth than to preserve what truly makes America great. I am ready to lead that fight."

In 2016, Weld was the vice presidential nominee on the Libertarian Party ticket with former New Mexico Gov. Gary Johnson. He previously served two terms as the governor of Massachusetts in the early 1990s.

Weld ran for Senate in Massachusetts in 1996 and lost against John Kerry. He later moved to New York and in 2005 unsuccessfully sought the Republican nomination for governor.

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