Mary Portas’ report into how to revitalise the high street has been delayed as the TV star wades through thousands of comments submitted to her website.

The so-called Queen of Shops was due to submit her report to the Prime Minister in the autumn, but is now expected to finish her investigations “by the end of the year”, said a spokesman for the Department for Business, Innovation and Skills (BIS).

“There are an awful lot of issues to consider and the report is still being written,” he said.

Portas has received nearly 2,000 comments on her website from members of the public and high street retailers since she was commissioned by the government to review the state of the UK high street and town centres, and come up with recommendations on how to improve them.

The star has also been travelling the country, touring town centres to speak directly to shoppers, local authorities and business owners.

Speaking during a visit to Rotherham in September, Portas said: "We have had a fantastic response to the review so far and received a huge number of ideas. I am actively encouraging everyone who cares about the future of the high street to have their say. I am working through all the ideas in the many contributions received and listening to key stakeholders, including big and small retailers.”

The star of shows such as Mary Queen of Shops and Mary Queen of Frocks has been asked to advise government in issues such as how to address the problem of vacant shops, prevent the proliferation of ‘clone towns’, and increase the number of small and independent retailers doing business in local town centres.

According to BIS, at the end of 2008, the average town centre vacancy was under 6%, but at the end of 2010 it was 14.5%. If the decline continues at this rate in two years’ time almost a third of UK high streets will be standing empty.