President Barack Obama demanded immediate action after learning the US government shutdown had cut off death benefits to relatives of soldiers recently killed in action, his spokesman said Wednesday.

Obama expected a solution by the end of Wednesday, Jay Carney said, adding the US leader was "disturbed" to find out the payments had stopped after budget funds for the Pentagon dried up.

The move followed media reports about the plight of four families who recently lost relatives serving in Afghanistan and were not able to access $100,000 in death benefits, housing allowances and financing for burial costs after the government closed a week ago.

"The president was very disturbed to learn of this problem and he directed the Department of Defense to work with the Office of Management and Budget and his lawyers to develop a possible solution," Carney said.

"The president expects this to be fixed today."

Carney repeatedly declined to say exactly when Obama found out about the issue.

He said the Pentagon had previously informed Congress that it would be legally unable to pay death benefits should the government close.

He also accused Republicans of causing the problem by shutting down federal operations by not passing a new budget before October 1, and for not including the provision in a bill already signed by Obama to ensure soldiers on deployment still get paid during the shutdown.

Since October 1, when the partial shutdown began, 17 troops have been killed abroad or on duty in the United States. None of their families have received the $100,000 payment usually given to survivors of dead service members.

The White House comment came as Defense Secretary Chuck Hagel travelled to Dover Air Force Base in Delaware on Wednesday to pay his respects to four soldiers killed recently in Afghanistan, said a Pentagon official, who spoke on condition of anonymity.

Hagel met with families of the four US Army soldiers at the Dover base, which processes the remains of all fallen troops.

The four soldiers, identified as First Lieutenant Jennifer Moreno, 25, Sergeant Patrick Hawkins, 25, Sergeant Joseph Peters, 24, and Private Cody Patterson, 24, were part of a joint special operations task force. They died on Sunday in the Zhari district in an explosion from a homemade bomb, according to the Pentagon.