Barack Obama made the plea on a visit to the National Institutes of Health (NIH), where he congratulated scientists on work towards a vaccine.
According to the WHO, 6,055 people have died in Liberia, Sierra Leone and Guinea.
The medical charity, Medecins Sans Frontieres (MSF), has again strongly criticized the international response.
It described it as patchy and slow, with the job of tackling the crisis largely left to doctors, nurses and charity organizations.
The MSF report said foreign governments – notably the UK in Sierra Leone and most recently China in Liberia – were continuing to build Ebola treatment centers.
However, these were sometimes in the wrong places and using under-qualified local staff.
Barack Obama said the strategy to fight Ebola was “beginning to show results”.
“We’re seeing some progress, but the fight is not even close to being over,” he said.
“Every hotspot is an ember that if not contained can become a new fire, so we cannot let down our guard even for a minute. And we can’t just fight this epidemic, we have to extinguish it.”
The president said it was encouraging to see declining infection rates in Liberia and called progress in vaccine research “exciting”.
He urged Congress to give a “good Christmas present” to the world by approving $6 billion in emergency funding.
Congress is at work on a massive spending bill, but Ebola legislation has become embroiled in political partisanship.
Conservative members of Congress are expected to challenge Barack Obama’s appeal for funds in response to the president’s recent controversial executive actions on immigration, helping more than four million illegal immigrants.
Meanwhile, the White House said that the US was better prepared to deal with an outbreak of Ebola at home, and efforts to battle it in West Africa were progressing.
A network of 35 hospitals across the US is ready to treat Ebola patients and the number of labs used for testing the virus has increased from 13 to 42.
w50tZonOgoUImage source: Wikimedia Commons President-elect Donald Trump celebrated his election victory at the Ultimate Fighting…
Millions of voters across the US chose to return Donald Trump to the White House…
Donald Trump declares victory in the US election as he addresses jubilant supporters in Florida.…
Stocks around the world are rising as Donald Trump appears to be on the cusp…
Donald Trump has won Pennsylvania, North Carolina and Georgia and taken a lead over Kamala…
Quincy Jones, the celebrated musician and producer who worked with Michael Jackson, Frank Sinatra, Ray…