WASHINGTON, United States (AFP) — President Joe Biden on Tuesday will unveil new rules easing the process for undocumented spouses of US citizens to obtain permanent residency status, the White House said.

The Biden administration has been trying to walk a thin line on immigration, a key issue for many Americans ahead of November’s presidential election.

The Democrat is seeking to be tougher on illegal migrants, while also contrasting himself with the harsher policies of Republican rival Donald Trump.

The new rules will not expand eligibility for permanent residency, but rather streamline the process for those who already qualify.

That includes by removing a requirement they leave the country as part of the application process.

The new rules would apply to those present in the country for at least 10 years and married to a US citizen before June 17, 2024 — which the administration estimates to include some 500,000 people.

In addition, some 50,000 stepchildren of US citizens would be eligible.

Those approved would be granted work authorisation and the right to stay in the United States for up to three years while they apply for permanent residency.

Once someone has permanent residency — also known as a green card — that person could in theory later apply for citizenship.

“What we are announcing are potentially streamlined processes… (to) minimise the bureaucracy, minimise the hardship that having to leave the country creates,” a senior administration official told reporters ahead of the announcement.

However, “only Congress can deliver… comprehensive reform of our immigration and asylum laws,” another official added.

A previous, bipartisan immigration package pushed by Biden in Congress would have introduced the strictest policies in decades, but fell apart when Republicans walked away from the deal.

More recently Biden signed an executive order shutting down the border to asylum seekers after certain daily limits are hit — a move that immediately drew criticism from the left and a legal challenge from rights groups.

The administration has defended its asylum order and characterised the congressional push as “the toughest and fairest set of reforms in decades”.

Trump meanwhile has referred to immigrants as “poisoning the blood of the country” and promised mass deportations of those in the country illegally.

The Biden administration is also on Tuesday set to simplify the process for children who came to the United States illegally as children — known as Dreamers — to get work visas if they’ve graduated college and have a “high-skilled job offer”.