In a letter, the finance group asked Mr Brown to increase the annual ISA limit to GBP9,000 from the current level of GBP7,000, to introduce a fairer regime of tax treatment on children’s savings, and to raise the stamp duty threshold to GBP206,000 in line with house price inflation.

While Nationwide welcomes the UK government’s proposals to simplify the ISA regime and extend the initiative indefinitely beyond its original 2010 commitment, it also believes that increasing the limits to GBP9,000 would be a fair response to savers’ interests and help encourage a more robust savings culture in the UK.

The bank also recognized that, although children can open a cash ISA at 16, as many as nine million youngsters in the UK aged under 18 are too old to qualify for a child trust fund but too young to invest in an ISA. As a result, parents saving for their children could find that the savings would become liable for tax on interest earned above their personal allowance on the investment. Nationwide has therefore called for the chancellor to equalize tax treatment for children, allowing families to save for the future without being penalized.

In addition, as part of its commitment to support affordable housing in the UK, Nationwide is also asking Mr Brown to increase the threshold at which the initial 1% tier of stamp duty tax paid on residential house purchases kicks in, in line with house price inflation. This would take the threshold up to GBP206,000 from its current level at GBP125,000.