Royal Bank of Scotland has launched a charter for small and medium sized enterprises that it claims will bring immediate help to around 20,000 start-ups annually amid persistent claims that banks are not doing enough to help businesses.

The giant bank, which is 70% owned by the government, has tried to demonstrate its commitment to SMEs with the first formal statement of the core business principles it will apply.

This includes the offer of free transactional banking for start-ups for two years, during which they will not have to pay for services like cheque processing.

The bank also hopes to demonstrate its commitment to the key SME market, and steal a march on rivals, by becoming the first to offer a cap on fees for arranging overdrafts and loans.

This will mean firms with turnover of up to £25m will not have to pay more than 1.5% of the value of any relevant borrowing facility annually, however many times it is reviewed.

The charter extends the bank’s commitment to offer customers with overdrafts the assurance that they will be maintained for 12 months and renewed at the same interest rate at the end of the term for a further year.

This measure was announced a year ago, since which time Royal Bank claims nine out of 10 small businesses have had their overdraft facilities renewed at the same or a lower rate.

The bank claimed this was evidence of a long-standing commitment to the sector, which was also reflected in the decision to maintain lending at high levels. The group said that its NatWest and RBS operations had lent £60bn to SMEs over the last two years.

Graham Galloway, managing director, business and commercial banking, for Royal Bank in Scotland, said: “Whilst we’ve led the field with a series of initiatives supporting them (customers) through the key stages of a recession, it’s important we continue to stay close to their needs and find new ways to support their growth in the months ahead.”

However, the charter announcement contained small print that might concern firms that may need to borrow.

The cap on arrangement fees is subject to a minimum fee of £150. There is no cap on other fees, such as monitoring or security fees.

Royal Bank said the cap does not apply “where we provide intensive support for businesses facing financial difficulties”.

It makes no commitment to impose a limit on margins on new lending, for example to a maximum percentage point premium over the base rate.

The charter has been launched at a time when banks continue to come under attack for their response to the recession. Critics claim many viable firms are still struggling to obtain credit on affordable terms.

The leaders of banks in which the government has acquired big stakes through tax-payer bail-outs have come under pressure from ministers to increase lending.

Claims by executives at Royal Bank and Lloyds Banking Group that demand for lending has dried up amid the recession have not silenced the critics.

Earlier this month Lloyds Banking Group, which owns Bank of Scotland, introduced a charter.

The bank – 43% owned by the taxpayer – said its plans would help “viable” businesses gain access to credit as the UK recovers from recession and give “clearer and fairer” prices.

The government is increasing its stake in Royal Bank from 70% to 84%.