Scores of American diplomats stationed across the globe have drafted a formal “dissent memo” to register their objections to President Donald Trump’s ban on Syrian refugees and travelers from seven Muslim-majority countries.

The draft memo, obtained by ABC News, represents the most significant opposition thus far from within the Trump administration to the president’s controversial executive order.

“This ban ... will not achieve its stated aim of to protect [sic] the American people from terrorist attacks by foreign nationals admitted to the United States,” wrote the diplomats. “It will immediately sour relations with these six countries, as well as much of the Muslim world, which sees the ban as religiously motivated.”

The draft memo does not contain any signatures, and its contents are categorized as “Sensitive But Unclassified.” The use of “dissent memos” at the State Department dates back to the Vietnam War, when they were considered necessary to ensure that diplomats on the ground had a means to express opinions that differed with formal U.S. policy.

To say that the writers of Monday’s dissent memo expressed opinions that differed with the Trump administration may be an understatement. “This ban stands in opposition to the core American values that we, as federal employees, took an oath to uphold,” they wrote.

“The end result of this ban will not be a drop in terror attacks against the United States; it will be a drop in international goodwill towards Americans and a threat towards our economy,” the memo read.

If the memo is formally submitted to secretary of state designee Rex Tillerson, who is currently awaiting Senate confirmation, the rules of dissent memos would grant Tillerson 30 to 60 working days to respond.

On Monday, a State Department spokesman said the agency is aware of the dissent memo. “The Dissent Channel is a longstanding official vehicle for State Department employees to convey alternative views and perspectives on policy issues,” spokesman Mark Toner said in a statement. “This is an important process that the Acting Secretary, and the Department as a whole, value and respect. It allows State employees to express divergent policy views candidly and privately to senior leadership.”

White House spokesman Sean Spicer was much less forgiving of the diplomats who are choosing to air their concerns. “They should either get with the program, or they can go,” Spicer said Monday at a press briefing.

Trump’s executive order, issued Friday, suspended travel to the United States from seven countries that have struggled to contain the rise of terrorist groups inside their borders: Iraq, Iran, Libya, Sudan, Somalia, Syria and Yemen. It also temporarily banned all refugees and indefinitely blocked Syrian refugees from entering the United States.

The order created chaos at U.S. airports over the weekend, as travelers from targeted countries were detained, and, in some cases, handcuffed. It also sparked massive protests at U.S. airports from people opposed to the ban.

Trump and members of his administration defended the blanket bans. “This is not about religion ― this is about terror and keeping our country safe,” Trump said Sunday.

Read the entire draft memo below.

This article has been updated with comment from Spicer and a State Department spokesman.