President Joe Biden has issued sweeping new executive actions aimed at curbing record migrant arrivals at the US-Mexico border that have left him politically vulnerable in an election year.
Under the new actions, officials can quickly remove migrants entering the US illegally without processing their asylum requests.
That will happen once a daily threshold is met and the border is “overwhelmed”, the White House said in a statement.
The US also unveiled new actions aimed at speeding up cases and easing pressure on overburdened US immigration courts.
Mr Biden spoke about the order at an event on Tuesday afternoon with several border town mayors. He said “this action will help us gain control of our border”.
Some immigration activists already have criticised the move, however.
“It’s unfortunate that politics are driving the immigration conversation in an increasingly restrictive direction,” said Jennie Murray, president and the CEO of the National Immigration Forum.
In his speech, the president criticised Republicans for not passing bipartisan immigration reform earlier this year – and he asked progressive critics of the new executive action to “be patient”.
“We’re wearing thin right now. Doing nothing is not an option.”
More than 6.4 million migrants have been stopped crossing into the US illegally during Joe Biden’s administration.
Migrant arrivals have plummeted this year, though experts believe that trend is unlikely to continue.
About a dozen advocates and Democratic lawmakers had their own press conference outside the US Capitol Tuesday, criticising Mr Biden’s decision.
Pramila Jayapal, the chair of the Congressional Progressive Caucus, said that she was “profoundly disappointed” by the executive action and called it a “step in the wrong direction”.
The campaign for Donald Trump, Mr Biden’s Republican challenger for the presidency, claimed on Tuesday morning, however that the order “is for amnesty, not border security”.
In its statement after the action was unveiled, the White House said that the new actions “will be in effect when high levels of encounters at the Southern Border exceed our ability to deliver timely consequences, as is the case today.”
Among the actions announced on Tuesday are the use of a 1952 law that allows access to the American asylum system to be restricted.
The law, known as 212(f), allows a US president to “suspend the entry” of foreigners if their arrival is “detrimental to the interests” of the country.
The same regulation was used by the Trump administration to ban immigration and travel from several predominantly Muslim countries and to bar migrants from asylum if they were apprehended crossing into the US illegally, provoking accusations of racism.
“While there’s no question the US needs to better address challenges at the border, the use of 212(f) authority is concerning,” Murray said.
Rep Jayapal, a Democrat, later told the BBC she is concerned about the actions sparking legal battles.
”When Donald Trump did this, the ACLU filed a lawsuit and it was declared unconstitutional…this is a different executive order. So things may be different,” she said.
But she added, ”we are at serious risk of being in violation of our own laws.”
The restrictions will come into effect when the seven-day average for daily crossings hits 2,500, US officials told reporters on Tuesday.
It will reopen to asylum seekers only when the average figure holds at 1,500 over a seven-day period, with the border re-opening to migrants two weeks later.
“These actions will be in effect when the Southern border is overwhelmed, and they will make it easier for immigration officers to quickly remove individuals who do not have a legal basis to remain,” the White House said.
Other actions include measures aimed at quickly resolving immigration cases in court, and expedited removals for those found to have no legal basis to remain in the US.
Asylum processing at ports of entry will continue under the order.
About 1,500 asylum seekers go through the process at official crossings each day, mostly after setting up appointments using a Customs and Border Protection (CBP) app known as CBP One.
Administration officials say the changes are likely to face legal challenges by immigration advocates or Republican-led states.
The administration plans to defend the new policies in court.
Guerline Jozef, executive director of Haitian Bridge Alliance – which works with Haitian migrants at the border – called the announcement “a direct assault on the fundamental human right to seek asylum”.
“This Trump era policy will leave thousands of vulnerable individuals, including families, children, and those fleeing violence and persecution, without the protection and refuge they need,” Ms Jozef said.
Speaking to reporters on Tuesday, senior administration officials pushed back on comparisons with Trump-era policies, noting that the new rules only apply during periods of increased arrivals.
They said that exemptions are made for unaccompanied children and those being trafficked.
Republicans, meanwhile, have criticised the Biden border plan as an election-year ruse.
They argue that US laws already exist to prevent illegal immigration but are not being duly enforced by the Democratic president.
The officials and the White House have sought to lay the blame on Republicans who stood in the way of a bipartisan border security deal that failed earlier this year.
“Republicans in Congress chose to put partisan politics ahead of our national security,” the White House said.
Recently released statistics from CBP show that about 179,000 migrant “encounters” were recorded in April.
In December, by comparison, the figure spiked to 302,000 – a historic high.
Officials in the US and Mexico have said that increased enforcement by Mexican authorities is largely responsible.
The decline in migrant crossings at the US border comes at a politically fraught time for President Biden.
Polls show that immigration is a primary electoral concern for many voters in the presidential election in November.
A Gallup poll at the end of April suggested that 27% of Americans view immigration as the most important issue facing the country, topping the economy and inflation.
A separate poll conducted in March by the Associated Press and NORC Center for Public Affairs Research indicated that two-thirds of Americans now disapprove of Mr Biden’s handling of the border, including about 40% of Democrat voters.