The Biden administration announced on Tuesday that it will implement a new asylum ban aimed at curbing the influx of migrants at the U.S.-Mexico border. The ban, set to take effect at 12:01 a.m. ET on Wednesday will block migrants from claiming asylum if they cross the border illegally until attempted crossings fall below specified thresholds.

The new policy allows authorities to quickly deport or return to Mexico any migrants who cross the border illegally without being given the opportunity to claim asylum. This ban activates when migrant arrests exceed 2,500 per day for a week. Current statistics show that border arrests averaged 4,300 per day in April, suggesting that the restrictions will take effect immediately.

The restrictions will remain in place until the average daily arrests drop below 1,500 for three consecutive weeks. The last time crossings were this low was during the early months of the COVID-19 pandemic in July 2020.

While the restrictions apply to illegal crossings between ports of entry, they do not block migrants who seek appointments to approach legal ports of entry via a government-run cell phone app. Additionally, those who have applied from abroad to enter through parole programs or hold temporary work visas will still be allowed entry. Unaccompanied minors, individuals facing serious medical or safety threats, and victims of trafficking are also exempt from the ban. Legal trade and travel across the border will not be affected.

However, key operational details remain unclear, including how the administration plans to deport migrants from distant or uncooperative countries and how many non-Mexican migrants Mexico will accept.

The American Civil Liberties Union (ACLU) has already signaled its intent to challenge the ban in court, likening it to similar asylum restrictions imposed by former President Donald Trump, which were also contested.

President Biden has been advocating for a Senate bill to strengthen border security, which includes provisions similar to the new executive actions. However, this bill has faced opposition, particularly from Republicans, who rejected it following Trump's opposition.

Immigration is a pivotal issue in the upcoming U.S. presidential elections. Recent polls indicate that voters prefer Trump's immigration policies over Biden's by a significant margin. Despite recent decreases in border crossings, which the administration attributes to increased enforcement by Mexico, Biden acknowledged in his asylum ban proclamation that the drivers of migration remain significant and challenging.

Republicans have broadly criticized Biden's immigration policies, with many claiming the new asylum restrictions are politically motivated and insufficient. Trump's campaign accused Biden of facilitating high levels of illegal immigration and suggested that the new measures are merely performative.

Democratic reactions are mixed. While more liberal lawmakers have criticized Biden, arguing that the ban undermines American values and endangers legitimate asylum seekers, moderates have praised the move. U.S. Senator Alex Padilla from California expressed concerns about legitimate asylum claims being ignored, while U.S. Representative Ruben Gallego from Arizona called the ban a "step in the right direction."