The Federal Emergency Management Agency (FEMA) will test an alert that would allow President Trump to communicate with you via your cellphone during national emergencies Wednesday afternoon.

FEMA pushed back the test of a national system last month. The test will allows "presidential alerts" to hit the majority of cellphones to October 3 at 2:18 p.m ET. The goal is to warn residents of national emergencies, such as dangerous weather.

The warning system "provides the president with the communications capability to address the nation during a national emergency," FEMA said in a notice posted on its website.

Some cellphone users will receive a message with a header that reads "Presidential Alert." The text then will say: "THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed."

But not everyone is on board with the notion of presidential notifications.

"I don't want this," actress Alyssa Milano tweeted on September 15. "How do we opt out, @fema?"

Seems like Milano is out of luck.

Under federal law, users can opt out of the alerts for "imminent threats" and AMBER alerts about abducted children but "not for presidential messages," FEMA warns.

This will mark the first national test of the so-called "wireless emergency alerts." Congress authorized the public safety alert system in 2008. It began operating in 2012 and has been used regionally.