Eleven Democrats in the Senate penned a letter to Secretary of State John Kerry Wednesday expressing "profound concern" regarding Iran’s ballistic missile test that violated United Nations sanctions.

The Hill reported that the senators, some of whom voted against the nuclear agreement with Iran, alleged that Tehran was using the test to gauge how the United States will respond to violations of the nuclear deal.

"We are concerned about the military significance of this test, which is part of a long-term Iranian program that seeks to improve the range and capabilities of its ballistic missiles," the senators, including vocal opponent of the deal Sen. Chuck Schumer (D., N.Y.), wrote.

"We are also convinced that the launch is an attempt to test the world’s will to respond to Iranian violations of its international commitments."

Last week, Samantha Power, U.S. ambassador to the United Nations, said that the ballistic missile test earlier this month represented a "clear violation" of U.N. Security Council resolutions. Diplomats from the United States, Britain, France, and Germany have demanded the U.N. Security Council take action in response to the violation.

While the Obama administration has acknowledged the likely violation, the White House has maintained that the missile test did not violate the nuclear deal with Iran.

The Democratic senators urged that the United States' ability to enforce the nuclear agreement with Iran "must be fortified by a zero-tolerance policy to respond to violations of the agreement and of applicable U.N. resolutions."

"There must be no ambiguity in our willingness to enforce Iran’s obligations under U.N. resolutions and the [Joint Comprehensive Plan of Action]," the senators wrote.

The letter comes two days after Sen. Bob Menendez (D., N.J.), who voted against the nuclear deal, demanded the Obama administration tighten sanctions on Iran in response to the missile test.

"The Iranian regime is drawing a line in the sand that demonstrates with malice that it will only selectively meet its obligations with respect to internationally sanctioned weapons programs," Menendez wrote in a letter to Kerry on Monday. "I write to recommend to you that you use the administration’s discretionary authority to tighten the full range of sanctions available to you to penalize Iran."

Iran has maintained that its test of a new domestically-produced surface-to-surface missile did not violate its nuclear agreement with world powers.

The letter sent Wednesday was signed by Sens. Michael Bennet (Colo.), Richard Blumenthal (Conn.), Cory Booker (N.J.), Ben Cardin (Md.), Christopher Coons (Del.), Ed Markey (Mass.), Chris Murphy (Conn.), Charles Schumer (N.Y.), Jeanne Shaheen (N.H.), Mark Warner (Va.), and Ron Wyden (Ore.).