Most investors will feel comfortable having built up an emergency fund equivalent to between three and six months of their salary before they started to invest for the long term.

These emergency funds are designed to ensure that they don't find themselves unable to fork out when their boiler breaks down or their car needs repairs.

For many savers however, they are unlikely to feel comfortable investing, even if they have this much money squirrelled away.

While the average UK salary is currently just over £37,000, savers say they need to have a cash pot worth £27,617 before they feel comfortable committing money to long term investment, according to research from Moneybox.

As many as 87 per cent of savers said they think a 'significant' cash safety net is essential to have before the start investing.

However, this reticence towards investing comes at a time when the Government is pushing hard to promote retail investing, and is considering making cuts to cash Isa allowances to do so.

The latest rumblings indicate that the Chancellor could slash the cash Isa allowance to just £12,000, according to the Financial Times, although a cut to £10,000 has not been ruled out.

A cut like this could be the biggest Isa overhaul for some 25 years.

The cash Isa, which offers tax-free saving of as much as £20,000 per year is integral to helping savers be financially resilient, Moneybox says.

Around £300billion worth of savings is currently held in cash Isas by savers, making them by far the most popular Isa product, ahead of stocks and shares and lifetime Isas.

Four in five savers told the firm they think cash savings are the foundation of their financial confidence, and almost half, some 44 per cent, said the ability to build up a substantial amount of savings will help to increase their motivation to invest.

Cecilia Mourain, chief savings officer at Moneybox, said: 'Cash Isas play a critical role in helping people build financial security and the confidence to take their first steps into investing.

'A strong cash foundation enables households to weather shocks and pursue long-term goals, from homeownership to retirement.'

Almost half of people with cash Isas, 48 per cent, said they used their cash Isa before starting to invest, with 65 per cent beginning to invest within two years of opening a cash Isa account.

As many as 80 per cent of savers said cutting the Isa allowance would undermine financial confidence.

Just nine per cent said a cut to the allowance would prompt them to invest.

She added: 'In a period of economic uncertainty, consistency and clarity in savings policy is essential. 

'Millions of people rely on the cash Isa to build their financial future, and any changes should be carefully considered to ensure they continue to support savers on their journey from building resilience through saving to long-term wealth.'

On average, Moneybox says people have between one and two cash Isas, and use them largely to build their cash savings.

Some 46 per cent of 18 to 34-year-olds said they use cash Isas to improve their financial discipline, while 42 per cent said they also use the savings products to save for specific ambitions like house deposits and weddings

Younger people hold an average of £26,897 in their cash Isas, while those from 35 to 64 have an average pot worth £39,996.

Somme 41 per cent of older people said they use their cash Isa for their emergency fund.