The group specifically criticized President Donald Trump's administration.
"Oxfam has monitored the response in Puerto Rico closely, and we are outraged at the slow and inadequate response the US government has mounted in Puerto Rico," Oxfam America President Abby Maxman said in a statement. "Clean water, food, fuel, electricity, and health care are in desperately short supply and quickly dwindling, and we're hearing excuses and criticism from the administration instead of a cohesive and compassionate response."
The group rarely criticizes government strategies in crises affecting wealthy nations such as the US.
"The US has more than enough resources to mobilize an emergency response but has failed to do so in a swift and robust manner," Maxman said.
Trump will be visiting Puerto Rico on Tuesday to survey the damage. During a briefing Monday afternoon, White House press secretary Sarah Sanders defended the administration's response.
"(President Trump) will assure the people there that we are with them 100% today and for the long haul. Puerto Ricans have shown incredible resilience, and we are fully committed to helping them rebuild their lives," she said.
Maxman said that Oxfam America will pursue its own two-pronged approach
to helping the island, which will consist of advocating for an overall improved response to the disaster and supporting local affiliates who are on site in Puerto Rico and can provide relief.
The organization will continue to push the government
, including Congress and other federal agencies, to provide better relief and remove any barriers in place that can inhibit progress.
"Oxfam has a long history of holding governments, including in the US, accountable to protect the most vulnerable in times of crisis," Scott Paul, humanitarian policy lead for Oxfam America, said in a statement to CNN. "Sometimes, that means helping them hold the government accountable, and in Puerto Rico, accountability is sorely needed."
This isn't the first time Oxfam has been critical of the Trump administration. The organization condemned the administration for slashing refugee admissions to the lowest level in history and last month it rented out the childhood home of Trump in Queens, New York
, and invited refugees to come and share their stories.