U.S. President Barack Obama declared a state of emergency in Michigan on Saturday and ordered federal aid for state and local response efforts in the county where the city of Flint has been contending with lead-contaminated drinking water.

Michigan Governor Rick Snyder had asked the president to declare both an emergency and an expedited major disaster in Genesee County to protect the safety of Flint residents.

Obama is authorizing the Federal Emergency Management Agency to coordinate disaster relief efforts there, the White House said in a statement.

The action is being taken to "lessen or avert the threat of a catastrophe in Genesee County," it said.

Snyder sent the Michigan National Guard to distribute bottled water and other supplies in the area earlier this week.

A financially struggling city, Flint was under control of a state-appointed emergency manager when it switched its source of tap water from Detroit's system to the nearby Flint River in April 2014 to save money.

Flint, which is about 60 miles (100 km) northwest of Detroit, returned to using that city's water in October after tests found elevated levels of lead in the water and in the blood of some children.