When the “Gang of Six” – a bipartisan group of senators – this week reached unexpected agreement on a $3,700bn package of fiscal reforms, it galvanised hopes that Congress and the White House could still strike a budget deal in time to avoid a default.

It also served as a reminder of the sweeping changes to government practices and programmes – from the way federal officials calculate inflation to the criteria they use to dole out unemployment benefits – that are being contemplated by lawmakers and the Obama administration as they seek to slash costs over the next decade.

Most in Washington do not think there is enough time – or sufficient political consensus – for the group’s full plan to pass both chambers of Congress and be signed into law by August 2, the deadline set by the Treasury beyond which it will not be able to pay its bills.