U.S. Senators Amy Klobuchar and Tina Smith, of Minnesota, are calling on President Donald Trump's administration to begin working with state leaders for a COVID-19 vaccine distribution plan.

The senators are calling on federal support to ensure Minnesota and other states can acquire the ultra-cold storage capability necessary for COVID-19 vaccines to be effective as they are distributed in the coming months.

The senators are also urging the Centers for Disease Control and Prevention to work alongside local governments and health care providers, as well as leaders in rural and underserved communities, to create the plan.

According to the senators, transporting, storing, and distributing vaccines at extremely cold temperatures creates a challenge for states working to develop and eventually implement their immunization programs.

"While we understand that some logistical details may be unknowable at this time given that a vaccine has yet to be granted an Emergency Use Authorization (EUA), it is alarming that the federal government has not provided more detailed guidance or additional resources to help state, territorial, and local governments understand the most likely mechanisms for distribution or requirements and recommendations for maintaining the cold chain, funding projections, or critical risks that should be addressed," the senators wrote, in part, in a letter.

"The time to get ahead of potential distribution issues and cold chain requirements is now. The federal government should be looking ahead to secure our supply chains and prepare to adequately transport and distribute whatever vaccine becomes available first," the letter states.

In addition to Klobuchar and Smith, the letter was signed by Senators Cory Booker (D-N.J.), Jeff Merkley (D-Ore.), Tammy Duckworth (D-Ill.), Mazie Keiko Hirono (D-HI), Kirsten Gillibrand (D-N.Y.), Chris Van Hollen (D-Md.), Sherrod Brown (D-OH), Elizabeth Warren (D-Mass.), Tammy Baldwin (D-Wis.), and Brian Schatz (D-HI).