(CBS) — Accusing the president of trying to divide the country ahead of the November elections, Mayor Rahm Emanuel called President Trump’s plan to issue an executive order ending the right of birthright citizenship “election season catnip.”

Trump, seeking to limit immigration to the U.S., is set to challenge a 150-year-old constitutional standard that anyone born in America is an American citizen. Mr. Trump told “Axios on HBO” that he plans to sign an executive order to “remove the right to citizenship for babies of non-citizens and unauthorized immigrants born on U.S.-soil.”

“How ridiculous, we’re the only country in the world where a person comes in, has a baby, and the baby is essentially a citizen of the United States for 85 years with all of those benefits,” the president said. “It’s ridiculous. It’s ridiculous. And it has to end.”

In a tweet Tuesday morning, Emanuel called the president’s plan “election season catnip.”

“Please. I know election season catnip when I see it. The President doesn’t have this authority, but he does have an interest in dividing the country and riling up his base. This is midterm election nonsense,” Emanuel posted.

Congressman Bill Foster, a Democrat from Naperville, called the president’s announcement “fear mongering,” and called on Trump to back down from his plan.

“This announcement is another example of the President’s attempt to walk away from the principles that made this country great and to instill fear in the immigrant community and the individuals who lawfully seek asylum in our country,” Foster said in a statement. “This announcement is also another stark example of the President’s willingness to stoke hatred among his political base at the expense of American values and our reputation as a leader of the free world. Since its founding, the United States has stood as a symbol of freedom and hope for anyone who sought safety from oppression and war.”

Trump told Axios he has talked with White House counsel about the executive order, and it is “in process… It’ll happen.”

The 14th Amendment, passed after the Civil War, specifically says that “all persons born or naturalized in the United States are citizens.” The Supreme Court has upheld this rule for legal permanent residents, but has never decided a citizenship case involving an illegal immigrant or a short-term visitor to the U.S.

The president’s comments come ahead of next week’s mid-term election, in which immigration is a key issue for his GOP base. On Monday, the administration announced it was deploying over 5,200 troops to the southern border to block the caravan of migrants, which is expected arrive at the U.S. next month.