Harpenden MP Peter Lilley has launched a furious tirade about questions into an increase in his expenses - claiming they were “pathetic”.

An analysis of local MPs’ expenses in a Herts Advertiser investigation shows that more than £1 million has been claimed by Mr Lilley and St Albans MP Anne Main during the past five years.

The findings reflect the latest figures released by the Independent Parliamentary Standards Authority (IPSA) in relation to staff, office costs, travel and accommodation.

IPSA is the body created by Parliament to independently oversee and regulate MPs’ business costs and expenses in the wake of the 2009 expenses scandal.

Given its regulatory role and aim to be transparent, the organisation publishes individual claims submitted by every MP.

Figures show that during the last parliamentary term, up to May 2015’s general election, Mr Lilley’s claims rose by 3.8 per cent for the most recent financial year, compared to the previous 12 months. Mrs Main’s rose by 0.5 per cent, compared to a national average rise of 1.6 per cent.

In the four years from 2011/12, Mr Lilley’s claims for office, staff, travel and accommodation costs rose 13 per cent from £129,000 to £146,000.

Figures for the past four years have been used, rather than five, because of a change in how staff costs were reported.

Also, the totals do not include the politician’s basic salary, which was set at £67,000 but recently climbed to £74,000 annually.

The Hitchin and Harpenden MP, who claimed £573,000 in his five-year term, saw his staff costs rise considerably during the last four years, from £110,000 in 2011/12, compared to £129,000 last year.

A breakdown of some of his claims shows that Mr Lilley made a £12.40 claim for a “book on global warming policies” in 2010/11.

The Tory MP has spoken regularly about climate change and has described himself as a ‘global lukewarmist’ rather than a climate change denier.

He also claimed £8.59 in 2011/12 for a “book on conquests and cultures” to help “contribute effectively to Parliamentary debates”.

When this paper contacted Mr Lilley’s office last week to seek comments on his expenses, specifically the rise in staff costs over the past few years, the recent 3.8 per cent increase in claims, and the rise in accommodation costs, from about £830 in 2013/14 to nearly £3,000 last year, the MP reacted angrily.

He replied: “Is this the best you can do! Is it true that I have only claimed for two books in five years – the last one in 2011? On my shelves I see X books on international development, Y on immigration, Z on the economy and A on other subjects I specialise on in Parliament.

“If I have failed to claim the cost of these as I should have done, I plead guilty – it is only because I am too busy trying to make well informed contributions to debate and answer pathetic enquiries like yours.”

Mr Lilley went on: “On staffing I recruited a research assistant at a low salary which I increased after one year as she was excellent. Sadly she was poached off me in August and I have not yet found a replacement so I fear my salary bill will have fallen this year as has, temporarily, my ability to do all I would like in Parliament.

“The reason we have a budget to employ staff is to do our job effectively.

“I describe myself as a ‘global warming lukewarmist’ – get a grip!”

• According to official Hansard reports on the House of Commons’ website, in a debate on November 5, 2009, Mr Lilley is asked by [former cabinet member] Frank Dobson whether he is a ‘global lukewarmist’, to which he apparently responded: “I am a global lukewarmist … a sort of sceptic”.