President Joe Biden on Tuesday will announce a program offering a path to citizenship to hundreds of thousands of immigrants in the US illegally who are married to US citizens, a large-scale legalisation effort that contrasts sharply with Republican rival Donald Trump’s plan for mass deportations.

The program, which will roll out in coming months, will be open to an estimated 500,000 spouses who have lived in the US for at least 10 years as of June 17, senior Biden administration officials said in a call with reporters on Monday.

Some 50,000 children under age 21 with a US-citizen parent also will be eligible, they said. The majority of people who would likely benefit are Mexicans, they added.

The program will allow the spouses and children to apply for permanent residence without leaving the US, removing a potentially lengthy process and family separation. They could eventually apply for US citizenship.

Biden, a Democrat seeking a second term in the White House, took office vowing to reverse many restrictive immigration policies of Trump, who is also seeking a second term in the White House. But faced with record levels of migrant arrests at the US-Mexico border, Biden has toughened his approach in recent months.

Earlier this month, Biden barred most migrants crossing the US-Mexico border from requesting asylum, a policy that mirrored a similar Trump-era asylum ban.

Biden’s planned legalisation programme for spouses of US citizens could reinforce his campaign message that he supports a more humane immigration system and show how he differs from Trump, who has long had a hardline stance on both legal and illegal immigration.

Biden is expected to make the announcement at a White House event on Tuesday tied to the anniversary of the Deferred Action for Childhood Arrivals (DACA) programme.

The DACA program was launched in 2012 by former President Barack Obama and then-Vice President Biden and currently grants deportation relief and work permits to 528,000 people brought to the US as children.

The Biden administration also is expected on Tuesday to roll out guidance that could make it easier for DACA recipients to obtain skilled-work visas.

US Representative Adriano Espaillat, a Democrat attending Tuesday’s event, said the relief for spouses is a way for the administration to balance out recent border enforcement measures.

Trump campaign spokesperson Karoline Leavitt called Biden’s new program “amnesty” in a statement and reiterated Trump’s deportation pledge, saying he would “restore the rule of law” if reelected.

A little more than half of US voters back deporting all or most immigrants in the US illegally, Reuters/Ipsos polling shows.

Still, separate polling by the advocacy group Immigration Hub found, opens new tab 71 per cent of voters in seven election battleground states backed allowing spouses in the US for more than five years to remain.

Rebecca Shi, executive director of the American Business Immigration Coalition, said focus groups conducted by her organisation with independent and Republican voters found they supported legal status for spouses.

“It boosts turnout in terms of Latino and base voters, but it also has support with the middle and the right,” she said on a call with reporters on Monday, adding that most people thought the spouses could already legalise.

Living in fear

One couple who could potentially benefit from the action was eagerly awaiting more details.

Megan, a social worker from the election battleground state of Wisconsin, met her husband, Juan, two decades ago when she worked with his cousin and uncle at a restaurant during her college summer break.

Juan’s family, from the Mexican state of Michoacan, had come to the US for generations as seasonal workers, with his grandfather participating in a US program for farmworkers. Juan was in the country illegally, but she never thought it would be an issue.

“I assumed maybe you pay a fine or something,” she said. “The punishment is just totally disproportionate.”

They have two daughters now —ages 4 and 7— and still have not found a way to fix Juan’s status. Reuters is withholding their names because of Megan’s concern they could face backlash.

Wisconsin does not issue driver’s licenses to immigrants in the US illegally, and the couple worry that Juan, who works as a landscaper, could one day be pulled over and deported.

She said the family likely would uproot and relocate to Mexico if Juan was ever sent back.

“It’s just a low-level stress that’s always there,” she said.