The UK Treasury has come under fire from MPs for refusing to attend a hearing to discuss the government’s proposed Energy Bill.

Economic Secretary Chloe Smith refused to attend the hearing this week, held by the Energy and Climate Change Committee, stating it would be improper for her to comment on another department’s legislation.

But this drew a stinging response from committee chairman Tim Yeo, who told Smith in a letter that “your refusal to give oral evidence will seriously inhibit the effectiveness of our inquiry”.

He said he was “very disappointed” at the Treasury’s decision and “somewhat perplexed” by Smith’s assertion that it would be improper to discuss legislation led by another department: in the past the Treasury has given evidence on solar tariffs to the Environmental Audit Committee.

He added that Treasury policies had a “dramatic impact” on the Energy Bill.

Yeo criticised the Treasury once again during the hearing itself, saying “the success of electricity market reform could well rest on Treasury decisions – such as how high to set the levy-cap on support for low carbon technology or whether the government directly underwrites new long-term energy contracts or not”.

He added: “The minister must not duck these vital questions on the Energy Bill – this legislation is far too important.”

Smith – who became the youngest member of the government when she was appointed Treasury Minister last November aged 29 – has attained some notoriety in the UK this week following an appearance on BBC television’s flagship current affairs programme Newsnight, where her inability to answer basic questions on a government freeze on fuel duty led to a backlash from Conservative MPs.

One said she had been “damaged” because “she really did slip up on the basic politics”, while another said that “whoever allowed her out on Newsnight should be taken out and shot”.

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