Labour MPs have asked Gordon Brown to rethink his decision to scrap tax breaks on childcare vouchers, warning that the move could cost the party crucial votes in the next general election.

According to reports, Patricia Hewitt, Estelle Morris, Hilary Armstrong, Beverley Hughes and Caroline Flint are among the signatories on the letter to the Progress think-tank.

They wrote: "We believe the government must look again at the decision, carefully considering the full impact of removing the tax relief on parents, employers and the childcare sector.

"Surely this is not the time for us to remove a key support from hard-working families at the very point we need them at their most engaged and productive to fuel the recovery from recession. Crucially, in the run-up to an election, it will remove support for working parents and for businesses in key marginal constituencies."

The government announced in September that tax and national insurance breaks on childcare vouchers will be withdrawn in stages from April 2011. Read more on that story.