Washington DC - House Republicans on Wednesday announced impeachment proceedings against President Joe Biden's homeland security chief as they seek to cement immigration as a major issue in November's presidential election.

Up to 10,000 migrants have been detained daily of late after crossing illegally from Mexico in what Republicans describe as a humanitarian disaster, while the White House and lawmakers have failed to agree on immigration reforms.

Republicans in Congress, who concluded a probe into Homeland Security Secretary Alejandro Mayorkas in December, accuse the Democrat of creating a national security emergency by ignoring immigration policy.

No impeachment vote has been scheduled, but House Homeland Security Committee chairman Mark Green said an initial hearing would be held next Wednesday.

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"Our investigation made clear that this crisis finds its foundation in Secretary Mayorkas' decision-making and refusal to enforce the laws passed by Congress, and that his failure to fulfill his oath of office demands accountability," he said.

A majority of the House would be required to vote that Mayorkas had committed "high crimes and misdemeanors," prompting a Senate trial that would boot him from office in the extremely unlikely case that two-thirds of senators voted to convict.

The proceedings add to Biden's election-year headaches as he faces his own Republican-led impeachment inquiry over unfounded allegations of corruption, amid record-low approval ratings.

In Eagle Pass, House Speaker Mike Johnson called on Biden to reinstate the abandoned Trump-era "remain in Mexico" policy keeping asylum seekers out of the country until their court appearances.

Still, the Biden administration has responded by pushing policies to fast-track border wall construction, criminalize asylum, and boost militarization of the US border and surrounding communities.

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But Johnson has said he won't accept anything less than the hardline border and immigration bill passed last year by House Republicans, a non-starter in the Senate.

Far-right Texas Governor Greg Abbott, meanwhile, has continued to send thousands of migrants to Democratic-led northern cities. He also signed a bill last month that would allow state police to arrest and deport migrants who cross illegally into the US from Mexico.

The Justice Department filed a suit against Texas on Wednesday, arguing that the bill known as SB4 is unconstitutional and only the federal government has the authority to regulate immigration.