Hillary Clinton on Thursday attacked Donald Trump's "loose talk" about using nuclear weapons, and said his constant threats to use nuclear weapons and tolerance for allowing other countries to develop these weapons is dangerous and would create a new international arms race.

"These may be the most reckless statements on national security by any major presidential candidate in modern history," Clinton wrote in a New York Daily News op-ed on Thursday morning. "Trump's policies would reverse decades of bipartisan consensus. Even letting friendly nations go nuclear would make it harder for us to prevent rogue regimes from doing the same."

Citing her experience as a senator in New York during 9/11, the Democratic front-runner explained that the next president must lead global efforts to improve and increase nuclear security, not encourage the use of such weapons.

"Don't hold your breath waiting for a similarly detailed plan from Trump or any of the other candidates," Clinton wrote. "But at a minimum we should expect anyone running for president to understand the stakes when it comes to nuclear weapons. Our national security is too important to entrust to someone who hasn't thought long and hard about how to keep us safe."

As the New York primary approaches on April 19, both Clinton and Trump lead their respective parties. Clinton is ahead of Sen. Bernie Sanders by about 13 points, while Trump has a 30-point lead over John Kasich and Ted Cruz. The NY Daily News editorial board endorsed Clinton in their Tuesday issue.