WASHINGTON -- President Barack Obama could declare a federal emergency in Flint, Michigan, as soon as this weekend in response to the area's water contamination crisis, the White House indicated Friday.

"The potential for that certainly exists," White House press secretary Josh Earnest said during his daily briefing.

Michigan Gov. Rick Snyder (R) called on the Obama administration Thursday night to declare an emergency over Flint's water situation. A spokeswoman for the Federal Emergency Management Agency told HuffPost on Friday that Snyder's request was under review.

“We’ve been actively engaged with the State of Michigan as it works to resolve the water issues in Flint," the spokeswoman said, noting that FEMA was already helping based on an earlier Snyder request to help coordinate federal agencies responding to the crisis.

Since October, Flint residents have been advised not to drink the brown stuff coming out of their taps, which they had previously been assured was safe even though it looked funny and caused rashes. The state admitted it made a mistake, and contributed to a public health emergency, when a local pediatrician reported unusually high lead levels in Flint children's blood.

Earnest said the federal government has already taken a number of steps to help with the situation, including providing bottled water and deploying FEMA personnel to Flint to serve as liaisons between local and federal officials. The Environmental Protection Agency will be assessing the impact of the contamination on the community, and the Justice Department is looking at "the decisions that led to this," he said.

Deadly neurotoxins contaminated the city's water after an emergency manager appointed by Snyder oversaw the city's switch from the Detroit water system to the Flint River, a decision city officials supported at the time. The state failed to ensure the city treated its new water for corrosion, and the new water wound up leaching lead from the city's pipes.

The EPA was aware of the lack of corrosion control and potentially high lead levels last year but stood by as state and local officials downplayed concerns.

Earnest wouldn't say whether the EPA screwed up.

"At this point, I'm quite limited in what I can say about attributing any sort of blame for this particular situation, primarily because the Department of Justice is taking a look at this question," he said. "The EPA has obviously been involved, and they're involved now, in trying to respond to the situation."

Flint switched back to the Detroit water system in October, but the high lead levels could remain for as long as six months. State police and the National Guard have been called in to distribute bottled water door to door.

UPDATE: 4:15 p.m. -- Members of the Congressional Black Caucus wrote to Obama on Friday calling for a thorough federal investigation of all entities that have oversight over Flint's water situation. They also urged immediate funding for Flint to help with its recovery efforts.

"The timeline for the water issues, which have led to a state of emergency being called for the City of Flint, are astonishing and unacceptable," reads the letter, signed by 44 members of the caucus. "The lack of proper oversight and action has led to tens of thousands of citizens being exposed to toxic levels of lead in their drinking water and demands a thorough federal response."

Their letter comes a day after Rep. Brenda Lawrence (D-Mich.) called for a congressional oversight hearing on Flint's water crisis.