"There is a glimmer of hope," Democratic Senator Chuck Schumer told NBC television a day after talks on funding the government to October 1 stretched into the night with the clock fast ticking down to a midnight Friday deadline.

Democratic Senate Majority Leader Harry Reid and Republican House Speaker John Boehner emerged from private negotiations Tuesday saying they had been "productive," and Schumer reported that staff-led discussions made "some progress."

US President Barack Obama, who said Tuesday he would call lawmakers back for White House talks if needed, has not done so, Schumer said, calling that "an indication that maybe there's a chance to avoid this shutdown, which we very much want to avoid."

An aide to Boehner, who has come under pressure from the archconservative

"Tea Party" movement not to compromise with Democrats, said no decision had yet been made on whether to hold another round of discussions at the White House.

The two sides have been feuding over a measure to fund the government for the rest of the fiscal year while making deep spending cuts to a range of domestic and foreign aid programs amid voter calls for Washington to get its fiscal house in order.

A current stopgap spending measure runs out at midnight Friday, triggering a partial government shutdown that Obama says could cripple the fragile US economic recovery and Boehner has warned may end up costing more than it saves.

Democrats complained Wednesday that Boehner had broken an agreement in principle to cut $33 billion and was now seeking $40 billion, while the speaker's office denied there had ever been a deal on the first figure.

"Every time we agree to meet in the middle, they move where the middle is," said Reid.

"The speaker has a choice to make, and not much time to make it. He can either do what the Tea Party wants or what the country needs."

Schumer said in his official Twitter feed that a "major sticking point" had to do with measures, approved by the Republican-held House of Representatives, rolling back environmental rules and stripping funds from the Planned Parenthood network of clinics that provide key women's health services because they offer abortion.