Sen. Bernie Sanders (I-Vt.) blasted President Trump's announcement Friday that he would not certify the multination Iran nuclear deal, saying Trump's comments amounted to "a lot of bluster."

Sanders argued that moving away from the Obama-era agreement would lift constraints on Iran's nuclear program and "irreparably harm America's ability to negotiate future nonproliferation agreements."

"If we are genuinely concerned with Iran's behavior in the region, as I am, the worst possible thing we could do is undermine this nuclear deal. It would make addressing all of these other problems harder. Unfortunately, I heard no strategy from Trump today, just a lot of bluster," Sanders said in a statement.

Trump announced earlier Friday that he would not certify Iran's compliance with the 2015 nuclear agreement, declaring that the deal was not in the national security interests of the U.S.

"We will not continue down a path whose predictable conclusion is more violence, more terror and the very real threat of Iran's nuclear breakout," Trump said.

However, the president stopped short of withdrawing the U.S. from the deal, which was established by a United Nations Security Resolution.

Trump also did not request that Congress impose additional sanctions on Iran for its nuclear activities, which would have effectively removed the U.S. from the deal.

The president instead asked Congress to pass new benchmarks for Iran to achieve in order to avoid nuclear-related sanctions down the road.

Despite the president stopping short of withdrawing the U.S. from the deal, Sanders said Trump's announcement on Friday further isolated the U.S. from its European allies, who played an integral role in brokering the deal with Tehran.

"Trump's decision also isolates the United States from some of its most important allies. France, the U.K. and Germany all continue to support the agreement and have consistently said that it is in their own national security interests," Sanders said.