Hitchin and Harpenden MP Bim Afolami has been appointed a parliamentary private secretary in the Department for Transport.

Mr Afolami, who has just returned to Westminster after the summer break, said he was delighted to announce his acceptance of the role – which will see him working with ministers headed by Transport Secretary Chris Grayling.

The 32-year-old Conservative said: “I will have the opportunity to work for people across Hitchin and Harpenden, giving a strong voice on local issues alongside the transport ministers.”

Parliamentary private secretaries act as a minister’s contact with MPs. The post is often seen as the starting point for MPs with ministerial aspirations.

Hitchin, Harpenden and the surrounding stations were some of the worst-hit amid the chaotic roll-out of a new timetable from May onwards.

Last week Mr Afolami joined fellow Tory MPs Heidi Allen, Stephen McPartland and Jonathan Djanogly in signing a letter to Mr Grayling calling for the upcoming rail fare increase to be delayed until “passengers have experienced three months of a reliable, sustained service that meets the levels expected due to the May timetable change”.

The letter quoted Network Rail statistics citing the Great Northern line, which serves Hitchin, as performing far below the national average.

It added: “Statistics only give a partial picture. The concentrated human cost of these percentages is played out in the massive impact that these delays and cancellations have had on our constitutents; missed business opportunities; lost work time; resignations; missed children’s bedtimes; stress-related illnesses; additional expense incurred through added travel arrangements. The toll has been huge.

“We cannot ask hard-pressed commuters to fund a fare increase on the back of this performance.”

In response to the letter, Hitchin Labour chairman John Hayes asked Mr Afolami on Twitter for clarification as to what would constitute a “reliable, sustained service”, and what Mr Afolami would do if Mr Grayling failed to make Great Northern operator Govia Thameslink deliver this.

Mr Hayes, who commutes by rail to work as a headteacher in north London, added: “Will it be OK to increase the fares after three months? Will the service be so improved that it can justify any kind of increase in charge?”

Mr Afolami is yet to respond to Mr Hayes’ questions.