Senior US military commanders have expressed frustration over the uncertainty that surrounds the Pentagon’s budget, warning that the current situation would impair readiness of the troops. 

US Army Chief of Staff General Mark Milley told the House Armed Services Committee on Wednesday that Congress’ failure to pass President Donald Trump’s budget would amount to “professional malpractice.”

Milley was one of the four commanders that warned the panel about the consequences of not passing the 2017 budget bill by the end of April and opting instead for a stopgap funding measure.

Trump’s proposed budget includes a $30 billion increase in the military spending that would push the base Pentagon budget for fiscal 2017 to $541 billion.

The raise comes at the expense of cuts to vital public funding, an issue that has drew warnings from both sides of the aisle.

Milley told lawmakers on Wednesday that continuing the stopgap funding would bring to a halt the Army's basic training by summer.

Also present at the session was the Air Force's General David Goldfein, who said without the new budget units not actively preparing to go into conflicts could be grounded by the same deadline.

A full-year continuation meant that the US Navy would not have the money needed to complete delivery of several ships and avoid buying numerous new one, warned Chief of Naval Operations Admiral John Richardson.

General Robert Neller, the commandant of the Marine Corps, told lawmakers that the lack of a budget would delay construction of specialized amphibious warships that Marines use during operations.

Shortly before the testimony began, an Air Force F-16 fighter jet crashed during a training mission southwest of Washington's Joint Base Andrews.

Referring to the attack, Goldfein reminded the lawmakers that it takes a lot of time and money to maintain the Air Force's fleet of aircraft, which are on average 27 years old.

Trump has pledged a "massive” increase in the pentagon’s budget spending to implement “the greatest military build-up in American history.”