Atlanta Congressman John Lewis is ramping up pressure on the Trump administration for its latest actions on the Southern border, assailing its new zero tolerance policy as “unbelievable” and “immoral.”

The Democrat said President Donald Trump is using the families illegally crossing the border to seek asylum, and particularly children who are being forcibly separated from their parents, as political pawns to extract money for a border wall from Democrats in Congress.

“These young children are being used for a political reason, to satisfy a political commitment that he made to his supporters that he would build a wall,” Lewis said of Trump in an interview with the Atlanta Journal-Constitution. “We don’t need to build a wall. We need to build bridges and reach out to people in other parts of the world.”

Lewis, an icon of the civil rights movement who is seen as a moral authority by many on Capitol Hill, said he thinks Trump “is just not telling the truth” about his immigration strategy and vowed to “do everything possible in my power and with my colleagues to stop this unbelievable, immoral action.”

'Zero Tolerance' Immigration Policy: Why Are Children Being Separated From Their Families

Lewis drew international headlines two summers ago for leading a sit-in on the House floor to protest the lack of action on gun control legislation. And he has dialed up his own rhetoric in recent weeks on immigration, raising alarm about what the Trump administration's policies could mean for metro Atlanta and marching through downtown Washington to protest the border separations.

He indicated on Monday evening that he has not ruled out another sit-in on immigration, but said he plans to huddle with his House colleagues first.

“I don’t know what we’re going to do, but we will do something,” he said. “Stay tuned.”

Democrats have upped the pressure on the Trump administration to overturn the policy. Most local GOP officials, meanwhile, have sought to dodge the issue ahead of a key meeting with Trump on Capitol Hill Tuesday. The debate has also infiltrated Georgia's gubernatorial race.

Trump on Tuesday continued to place the blame on Democrats for being too lax on immigration laws.

"Democrats are the problem," he tweeted. "They don't care about crime and want illegal immigrants, no matter how bad they may be, to pour into and infest our Country, like MS-13. They can't win on their terrible policies, so they view them as potential voters!"

The president said the responsibility lies with Congress, not his administration, to make the first move on immigration.

"Now is the best opportunity ever for Congress to change the ridiculous and obsolete laws on immigration," he said Tuesday ."Get it done, always keeping in mind that we must have strong border security."

Lewis said many of the images being captured on the border remind him of his own experiences in the South during the 1960s.

“I just feel that history will not be kind to us as a nation and as a people if we continue to go down this road,” he said. “We can do better. We can do much better.”

The border crisis is just the latest instance in which Lewis has tangled with Trump. Lewis said shortly after the election that he did not see Trump as a "legitimate president," boycotted the New Yorker's inauguration and State of the Union addresses and canceled plans to attend the opening of a civil rights museum in Mississippi last year because he would have had to share a stage with his rival. Trump fired back at Lewis' initial snub, calling the Democrat's Atlanta-based 5th Congressional District "crime infested."

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