A controversial Trump-era immigration policy known as Title 42 expired on Thursday.

Border authorities will now be applying new measures that will deny asylum to those arriving at the US-Mexico border without having first applied online or without seeking protection from the country being passed through.

The new restrictions will apply to the vast majority of non-Mexican migrants due to their passage through multiple countries en route to the United States.

The announcement comes as Texas Governor Greg Abbott deployed new forces to the border with Mexico on Monday to prevent the entry of migrants.

What are 'Title 42' restrictions

Since March 2020, Title 42 restrictions have allowed US authorities to expel non-Mexican migrants to Mexico without the chance of seeking asylum in the US.

Under this system, asylum seekers had to prove exceptional circumstances — such as having a disability, being pregnant, or facing the threat of violence — while navigating an opaque network of churches, attorneys and migrant shelters in order to receive an exemption to the Title 42 rules.

The Biden administration kept the measures in place but indicated that because the policy was a public health measure and not an immigration enforcement measure, it could not be extended indefinitely.

Under the new regulations migrants caught crossing illegally will not be allowed to return for five years, and they can face criminal prosecution if they do.

In January the US launched an online system allowing migrants at the border with Mexico to apply for asylum online.

Large number of asylum seekers expected

While the new measures are meant to change the way migrants go to the southern border, officials are bracing for a large amount of migrants along the border with Mexico.

The US is sending 1,500 troops to support US Customs and Border Protection personnel at the southern border.

"It's going to be chaotic for a while," US President Joe Biden said on Tuesday.

Meanwhile, joint efforts to curb undocumented migration through Latin American countries do not appear to be working.

Reuters news agency cited Panama's Security Ministry as saying that 40,297 migrants reached Panama through the jungle connecting it with Colombia during April.

Reuters reported that the number is up more than six times when compared with the same period last year, and that's despite a two-month campaign announced in April to tackle undocumented migration through the region involving the US, Panama and Colombia.

Border protection measures criticized

Some Democrats and immigration activists have criticized Biden for gradually toughening his approach to border security.

Earlier this month Democratic Senator Bob Menendez, the chair of the Senate Foreign Relations Committee, labeled Biden's decision to send troops to the border as "unacceptable."

Migrant advocacy group Border Network for Human Rights (BNHR) has condemned the Biden administration's move to send more military personnel to the border region and has instead called for "humanitarian and welcoming infrastructure."

"If our federal government was genuinely committed to addressing this humanitarian crisis with dignity, instead of increasing the presence of military personnel at our southern border, they would have sent additional lawyers, healthcare providers, and coordinated emergency response teams to welcome refugees at our border," BNHR said in a statement earlier in May.

kb/jcg (AP, Reuters)