A group of 20 Republican senators led by Chuck GrassleyChuck GrassleyOvernight Cybersecurity: Kushner says no collusion, improper contacts with Russia | House poised to vote on Russia sanctions | U.S., Japan to beef up cyber cooperation Mattis rips Pentagon officials for M wasted on Afghanistan camouflage Feinstein calls for Sessions to appear in front of Senate Judiciary Committee MORE (R-Iowa) sent a letter to President Obama late Tuesday questioning the legality of his recent directive to stop deporting illegal immigrants who come to the country at a young age.

“Not only do we question your legal authority to unilaterally act in this regard, we are frustrated that you have intentionally bypassed Congress and the American people,” the letter read in part. “As president you swore to uphold and defend the constitution and enforce laws. Your recently announced directive runs counter to that responsibility.”

The letter requests documents from President Obama proving that he sought legal counsel to ensure that he had the right to issue the immigration directive.

Obama announced on Friday that his administration would stop deporting illegal immigrants who come to the country at a young age and meet certain requirements. The policy change will apply to those who came to the United States before they were 16 and who are younger than 30 if they have lived here for five years, have no criminal history, graduated from a U.S. high school or served in the military.

The change in policy could allow as many as 800,000 immigrants who came to the United States illegally not only to remain in the country without fear of being deported, but to work legally.

The letter alleges that Obama’s directive “runs contrary to the premise that American workers must come before foreign nationals.”

“It is astonishing that your administration would grant work authorizations to illegal immigrants during this time of record unemployment,” the senators said.

The senators laid out dozens of questions for the administration in regard to the policy, and requested Department of Homeland Security secretary Janet Napolitano and two immigration officials be made available to respond.

The GOP has struggled with how to respond to the administration’s policy announcement.

On Tuesday, Senate Minority Leader Mitch McConnellMitch McConnellMcCain returning to Senate in time for health vote Senate Dems launch talkathon ahead of ObamaCare repeal vote Overnight Healthcare: Trump pressures GOP ahead of vote | McConnell urges Senate to start debate | Cornyn floats conference on House, Senate bills | Thune sees progress on Medicaid MORE (R-Ky.) said Republican lawmakers would wait to weigh in on it until they heard from Mitt Romney on the issue. Romney avoided taking a clear stance on the issue in interviews over the weekend, but will meet with Hispanic leaders on Thursday and is expected to reveal his position on Friday.