Washington (CNN) Former South Carolina Republican Rep. Mark Sanford, who is considering mounting a challenge to President Donald Trump in 2020, warns of a looming financial crisis for America if the country doesn't try tackling its mounting debt.

"There's a big storm coming," Sanford says in a campaign style video released Monday, adding that America is "in the most precarious financial position" and "not dealing with it could crush our economy, it could wipe out whatever we've saved, it could even destroy our republic."

The former congressman has been privately considering whether to run since leaving office in January. Sanford's presidential bid would be a long shot against Trump, who has 88% of approval among Republican voters.

Sanford told CNN's Jake Tapper that he's been encouraged to run for president by people who "have said we need to have a conversation about what it means to be a Republican."

"Because the bent that we've been moving toward here of late is not consistent with the values and the ideals they believed in for a very long time," Sanford said Tuesday on CNN's "The Lead."

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