Republican presidential candidate Vivek Ramaswamy is proposing raising the legal voting age to 25, his campaign announced Thursday.

His proposal would allow 18-year-olds to vote if they met a "national service requirement" -- if they're an emergency responder or served at least six months in the military -- or they pass the naturalization exam, the test immigrants must pass to become US citizens. The change would require a constitutional amendment, making its enactment unlikely.

Ramaswamy, a biotech founder, entered the race in February and has used his wealth to fund his bid and aggressively campaign in Iowa, New Hampshire, and South Carolina -- states that will be key to securing the GOP nomination. He said he would provide the "rationale and detail" for his voting proposal during his Thursday night rally in Urbandale, Iowa.

"Our military currently suffers a 25% recruitment deficit, and only 16 percent of Gen Z say they're proud to be American. The absence of national pride is a serious threat to the future of our country," Ramaswamy said in a statement released by his campaign. "We must think ambitiously about reviving civic duty in America."

The 26th Amendment, ratified in 1971, lowered the voting age from 21 down to 18, although some states let people who are 17 vote in primaries if they'll be 18 on Election Day.

Politico first reported that Ramaswamy was planning to announce this new proposal, despite his staff objecting to the idea.

He has pitched himself as an outsider, having never held political office, and the candidate to take Donald Trump's "America First" policy further than the former Republican president. Among his other proposals, he has floated shutting down federal agencies such as the Education Department, the Federal Bureau of Investigation and the Bureau of Alcohol, Tobacco, Firearms and Explosives.

In his campaign speeches, he's lamented over what he has described as a "national identity crisis" and has argued that the US needs to unite around its basic ideals of meritocracy, rule of law and free speech.

"Civic Duty Voting can create a sense of shared purpose and responsibility amongst young Americans to become educated citizens," he said in the Thursday statement.