The Labour MP for Mitcham and Morden racked up the biggest bill for paper, envelopes and postage in the course of a year, figures from Parliament reveal.

Siobhain McDonagh used £35,207 of envelopes with pre-paid postage and another £13,900 on stationery during the last financial year.

She was also the biggest stationery spender in 2003/04 with a bill of £31,845 and came second in 2004/5 with £37,442.

Ms McDonagh has held the seat since 1997 and has a 12,560 majority.

A spokesman said the stationery had been used to contact constituents about significant local issues.

This included the potential closure of St Helier Hospital and the proposed Eastfields railway station in Mitcham, both of which have had successful outcomes.

The MP also launched a consultation on two local schools with flagging performances.

"Siobhain sends out lots of letters to her constituents because she wants to be the hardest working MP that she can," he said.

"If she did not contact them, she feels she would not be doing her job properly."