Eighty chief executives, from companies including Microsoft, JP Morgan and GE, have waded into the presidential election campaign with a call on Washington to use tax increases and spending cuts to address the US's $16tn debt.

The intervention, less than two weeks before election day, comes as Barack Obama and Mitt Romney have faced criticism for the scant details of their financial plans to tackle America's massive debt. According to the CEOs, no solution can be found without tax hikes, which Romney opposes, and cuts to public spending.

The letter has been signed by many of the biggest names in US business, including Steve Ballmer, CEO of Microsoft, JP Morgan's Jamie Dimon, and Lloyd Blankfein at Goldman Sachs. According to the signatories, any plan has to "include comprehensive and pro-growth tax reform, which broadens the base, lowers rates, raises revenues and reduces the deficit" as well as limiting the growth spending in areas including healthcare.

"Policymakers should acknowledge that our growing debt is a serious threat to the economic wellbeing and security of the United States," says the letter, put out by nonpartisan lobby group Fix The Debt.

"It is urgent and essential that we put in place a plan to fix America's debt. An effective plan must stabilize the debt as a share of the economy, and put it on a downward path."

The CEOs are stepping into a debate that has caused gridlock in Washington. At the end of the year, Bush-era tax cuts are set to expire and draconian spending cuts will be imposed unless a political solution is found. The so-called "fiscal cliff" could plunge the US back into recession, according to the Congressional Budget Office.

Romney and his running mate Paul Ryan have signed a pledge with lobby group Americans for Tax Reform not to increase taxes.

Obama has proposed raising the marginal income-tax rates for the top 2% of taxpayers. None of the CEOs endorse that plan either, and have instead called for an overhaul of the tax code that would eliminate or reduce deductions, credits and loopholes.

The CEOs endorsed the bipartisan plan to tackle the deficit drawn up in 2010 by Republican Alan Simpson and Democrat Erskine Bowles. The Simpson-Bowles plan called for roughly $3 in spending cuts for every $1 in tax increases.

"When you talk about a $16tn debt, I don't see how you can avoid addressing both sides," said Randall Stephenson, CEO of AT&T.

"The recommendations of the bipartisan Simpson-Bowles Commission, which saved $4tn and addressed all parts of the budget, provide an effective framework for such a plan," said the CEOs.

"The plan should be conducive to long-term economic growth, protect the vulnerable, include credible enforcement mechanisms to ensure that debt reduction is achieved and leave the next generation better."

Gus Faucher, a senior macroeconomist at PNC Financial said the letter was unlikely to change the course of the debate before the election but in the long term he expected whoever is elected to be forced to look at both tax hikes and spending cuts.

"The big issue is how we pay for retiring babyboomers, and I don't think as a society we have really faced up to that yet. Nothing will get done until after the election but it's difficult to see a solution that only involved spending cuts," he said.