President Joe Biden on Saturday blamed "a small group of extreme Republicans" for a budget impasse that has placed the US government a week away from a shutdown, urging the lawmakers to solve the issue.

Speaking at a Congressional Black Caucus awards dinner, Biden said he and top House Republican Kevin McCarthy had previously agreed on government spending levels.

"Now a small group of extreme Republicans don't want to live up to the deal so now everyone in America could be forced to pay the price," he said.