AUSTIN, TEXAS - JUNE 08: Texas Gov. Greg Abbott speaks during a news conference at the Texas State Capitol on June 08, 2023 in Austin, Texas. Gov. Abbott and Texas Department of Public Safety Director Steve McCraw joined bill authors, sponsors, legislators and law enforcement members in the signing of bills designated towards enhancing border security along the southern border. (Photo by Brandon Bell/Getty Images)
CNN  — 

Texas Gov. Greg Abbott is expected to endorse Donald Trump on Sunday, during an anticipated visit from the former president to the border city of McAllen, two sources familiar with the matter told CNN.

The endorsement would be a major boon to the Trump campaign, especially given the Texas Republican governor has long been close with Florida Gov. Ron DeSantis, one of Trump’s GOP primary rivals.

The trip is being dubbed as an official state visit, a source said, and Trump and Abbott will appear together while discussing future plans for curbing illegal immigration. Both have come under fire in recent days for their policy approaches to the US border with Mexico, as an ongoing surge of migration has placed immense pressure on local and federal resources.

Trump has escalated his sharp immigration rhetoric in recent weeks. The GOP front-runner has publicly said he wants to revive many of his first-term immigration policies to restrict both legal and illegal immigration — including reinstating and expanding a travel ban on predominantly Muslim countries and bringing back a Covid-era policy known as Title 42 to further restrict immigration into the country, though this time it would be based on the assertion that migrants carry other infectious diseases.

CNN reported on Saturday that he is planning a widespread expansion of his first administration’s hardline immigration policies if reelected in 2024, including rounding up undocumented immigrants already in the US and placing them in detention camps to await deportation, according to a source familiar with the plans.

Meanwhile, Texas has been locked in a hard-fought legal battle with the Biden administration over its efforts to curtain illegal immigration. In the latest development, Abbott is expected to take the extraordinary step of signing a bill that would make it a new state crime to enter Texas illegally and give local law enforcement the power to arrest and order migrants to leave the United States.

This story has been updated with additional information.

CNN’s Rosa Flores and Sara Weisfeldt contributed to this report.