(U.S. Marine Corps photo by Cpl. Cutler Brice)

President Donald Trump's decision to send troops to the southern border and funding transfers following the declaration of a national emergency pose an "unacceptable risk to Marine Corps combat readiness and solvency," the Marine Corps commandant warned.

An internal memo sent in March 2019 by Marine Corps Gen. Robert Neller to Secretary of the Navy Richard Spencer and Acting Secretary of Defense Patrick Shanahan listed "unplanned/unbudgeted southwest border operations" and "border security funding transfers" alongside Hurricanes Florence and Michael as "negative factors" putting readiness at risk, the Los Angeles Times first reported.


The four-star general explained that due to a number of unexpected costs, referred to as "negative impacts," the Marines will be forced to cancel or limit their participation in a number of previously planned activities, including training exercises in at least five countries.

(U.S. Marine Corps photo by Sgt. Asia J. Sorenson)

He warned that the cancelled training exercises will "degrade the combat readiness and effectiveness of the Marine Corps," adding that "Marines rely on the hard, realistic training provided by these events to develop the individual and collective skills necessary to prepare for high-end combat."

Neller further argued that cancellations or reduced participation would hurt the Corps' ties to US allies and partners at a critical time.

Border security is listed among several factors, such as new housing allowances and civilian pay raises, that could trigger a budget shortfall for the Marine Corps, but it is noteworthy that the commandant identified a presidential priority as a detriment to the service.

In a separate memo, Neller explained that the Marines are currently short $1.3 billion for hurricane recovery operations.

"The hurricane season is only three months away, and we have Marines, Sailors, and civilians working in compromised structures," he wrote.

Marines help push a car out of a flooded area during Hurricane Florence, at Marine Corps Base Camp Lejeune, Sept. 15, 2018.

(U.S. Marine Corps photo by Lance Cpl. Isaiah Gomez)

The Pentagon sent a list of military construction projects that could lose their funding to cover the cost of the president's border wall to Congress on March 18, 2019. Among the 400 projects that could be affected were funds for Camp Lejeune and Cherry Point Marine Corps Air Station, both of which suffered hurricane damage in 2018.

Congress voted in March 2019 to cancel Trump's national emergency, but the president quickly vetoed the legislation.

Critics have argued that the president's deployment of active-duty troops to the border, as well as plans to cut funding for military projects, are unnecessary and will harm military readiness.

In October 2018, more than 5,000 active-duty troops joined the more than 2,000 National Guard troops already at the southern border.

The deployment, a response to migrant caravans from Central America, was initially set to end in mid-December 2018, but it has since been extended until at least September 2019 As of January 2019, border operations have already cost the military $230 million, and that figure is expected to grow throughout 2019.

This article originally appeared on Business Insider. Follow @BusinessInsider on Twitter.