(CNN) -- The Biden administration has decided to appeal a federal court decision that blocked the use of a controversial Trump-era policy allowing for the swift removal of migrants at the US-Mexico border.
Last month, US District Judge Emmet Sullivan blocked the authority, known as Title 42, but agreed to a Biden administration request that he pause his ruling for five weeks so that the government can prepare to comply with it.
Wednesday, the Justice Department told the court it planned to appeal.
"The government respectfully disagrees with this Court's decision and would argue on appeal, as it has argued in this Court, that CDC's Title 42 Orders were lawful ... and that this Court erred in vacating those agency actions," the Biden administration said in a court filing.
Title 42 -- which has been heavily criticized by public health experts and immigrant advocates -- has largely barred asylum at the US-Mexico border, marking an unprecedented departure from traditional protocol.
But while its origins were in the Trump administration, Title 42 has become a key tool for the Biden White House as it faces mass migration in the Western hemisphere. Officials have been bracing for an influx of migrants when the authority lifts.
Several Republican-led states have asked the court to let them intervene in the case striking down the Title 42 ruling, so that the states could defend the Trump-era policy.
In their request to intervene, the Republican states pointed to the separate litigation they had brought challenging the Biden administration's efforts to end the authority, which resulted in a court order from a separate court blocking Title 42's termination earlier this year.
"Because invalidation of the Title 42 Orders will directly harm the States, they now seek to intervene to offer a defense of the Title 42 policy so that its validity can be resolved on the merits, rather than through strategic surrender," they wrote.
The states seeking to defend the policy are Arizona, Louisiana, Alabama, Alaska, Kansas, Kentucky, Mississippi, Nebraska, Ohio, Oklahoma, South Carolina, Texas, Virginia, West Virginia, and Wyoming.
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