The USNS Comfort hospital ship "will return to South America this fall," Pentagon spokeswoman Commander Sarah Higgins said.

"We are working the details in close coordination with our Colombian partners."

Defense Secretary Jim Mattis, while on a trip to South America last week, said the deployment is "an effort to deal with the human cost of (Venezuelan President Nicolas) Maduro, and his increasingly isolated regime."

"This is a very specific effort to try to help our neighbors, who are doing their best, I think, to help these refugees," he added.

According to Pentagon spokesman Colonel Rob Manning, the hospital ship will provide life-saving treatment and medical care to thousands of people.

"Our service members and medical professionals, doctors and nurses, will work alongside regional partners to support ongoing humanitarian response efforts to include addressing the impact of the Venezuelan humanitarian crisis," he said.

The mission marks the sixth hospital ship deployment to the region since 2007.

The United Nations estimates that 2.3 million Venezuelans have fled an economic and political crisis looking for work and to escape poverty, and Colombia has given temporary residence to more than 800,000 Venezuelans.