Via Univision English News (same link as above) the American Association of Immigration Lawyers (AILA)says:

"The Trump government is using the caravan of desperate people hundreds of miles away as an excuse to destroy our nation's laws and prevent asylum-seekers from obtaining a fair asylum opportunity," the organization said. "The United States asylum law guarantees a fair and meaningful opportunity to seek asylum, even for those who enter through places outside the ports of entry," it added.

AILA says that, while "not everyone is eligible for asylum, all people who come to the border deserve their asylum claim to be heard. The government's attempt to end that fundamental American value of due process is reprehensible. "

"Forcing asylum seekers to show up at ports of entry means that even more people will be rejected, something that the administration is already doing," it added.

A lawsuit challenging the proclamation was filed today by several groups in the Northern District of California.

The case, East Bay Sanctuary Covenant v. Trump, was filed in federal court in San Francisco. It was brought on behalf of East Bay Sanctuary Covenant, Al Otro Lado, Innovation Law Lab, and the Central American Resource Center in Los Angeles.

The ACLU has made the Complaint available here.