Democratic presidential hopeful Mayor of South Bend, Indiana Pete Buttigieg participates of the sixth Democratic primary debate of the 2020 presidential campaign season co-hosted by PBS NewsHour & Politico at Loyola Marymount University in Los Angeles, California on December 19, 2019.

Democratic presidential contender Pete Buttigieg unveiled his immigration plan on Sunday, including a path to citizenship for the country's 11 million undocumented immigrants.

"Our policies should acknowledge that immigrants are not outsiders," Buttigieg wrote in the plan.

The mayor of South Bend, Ind., released the plan as the Democratic presidential primary heats up. On Thursday, Buttigieg came under fire from all sides during the sixth debate of the race, hosted in Los Angeles.

Buttigieg is in fourth place in national surveys, but recently surged in the early caucus and primary states of Iowa and New Hampshire, where polls put him in first place and second place, respectively. His support to date has been weakest among voters of color.

Buttigieg said at the debate that families separated by the Trump administration's immigration policies should have a "fast track to citizenship because what the United States did under this president to them was wrong."

Similarly, the plan released on Sunday focuses on "family unity." It also notes the potential benefits to the economy that could come from revamping the immigration system.

It calls for a reversal of a number of Trump administration policies — including a halt in border wall construction — and puts an emphasis on foreign affairs, specifically addressing "root causes" for why some immigrants flee their homes and countries.

The agenda builds on Buttigieg's previously released plans, including his "Douglass Plan" for black America and a Latino-focused proposal released earlier this month.

On his first day in office, Buttigieg wrote, "we will reverse this administration's cruel and counterproductive immigration actions that take infants out of their mothers' arms, argue against children having toothpaste or soap, deport veterans, break up families, and sweep up workers in raids while leaving exploitative employers unpunished."

"But we will do more than simply end these outrages," he wrote.

In addition to the path to citizenship, which Buttigieg pledged to pursue in his first 100 days in office, the agenda includes the following proposals, among others:

A National Office of New Americans to coordinate federal, state and local efforts promoting immigrant and refugee "integration and inclusion."

A new review system for employment-based visas, to set allotment every other year based on "labor market needs, engagement with immigrant and other stakeholders, and analysis of domestic and global trends."

Acceleration of family reunification by increasing the number of family visas that are issued and ending certain three-year and 10-year bars on reentering the U.S. that are sometimes triggered via the application process for family green cards, which can require leaving the country.

Ending private, for-profit prison contracts for immigrant detention centers.

Stop construction of the U.S.-Mexico border wall, and invest in "technology-driven border solutions."

Offering 'deferred action' from immigration enforcement to those who have lived in the U.S. for years and to vulnerable populations and those with strong ties to the community

Pursuing civil rights reforms, such as supporting the right to counsel for those facing deportation, making the immigration court system independent and reviewing the Trump administration's deportation decisions.

Reinstating aid to Central America that the Trump administration suspended

"Most Americans welcome refugees, and they abhor family separation," the plan reads. "Yet Congress has failed to act. Since the last comprehensive reform, decades ago, the population of undocumented immigrants has stabilized at nearly 11 million people."

Buttigieg wrote that the plan will "foster belonging for all Americans" and is "also good for our economy."

"In his first 100 days, Pete will push for legislation that provides a mechanism to gain legal status and ultimately citizenship, including for people with temporary protections — Deferred Action for Childhood Arrivals (DACA), Temporary Protected Status (TPS), Deferred Enforced Departure (DED), and withholding of removal," the plan reads.

Congress has struggled for years to tackle immigration, frustrating successive presidents.

Former Vice President Joe Biden, as well as Sens. Bernie Sanders and Elizabeth Warren, released their immigration plans earlier this year.