A fictional documentary that imagined life under a Ukip government has received a backlash over its alleged "political bias" and "flawed" approach.

Attracting 18 complaints before the show even aired, Ukip: the First 100 Days was advertised as a "ground-breaking and provocative fictional documentary", set in a "fictional future where Ukip have won the 2015 general election and Nigel Farage is prime minister".

Media watchdog Ofcom confirmed that following the broadcast it had received over 700 complaints about Ukip: the First 100 Days from people claiming it was politically biased.

A spokesman said: "Ofcom has received 731 complaints about UKIP: the First 100 Days on Channel 4. We will assess these complaints before deciding whether to investigate."

The fictional documentary, which aired at 9pm on Monday 16 February, combined acted scenes with actual news footage and showed race riots breaking out in Britain as Ukip's policies took effect.

Senior Ukip MEP Roger Helmer said on Sunday that the film was a "hatchet job" on the political party, and tweeted: "Fortunately the Great British public recognise agitprop when they see it. And ignore it."

However a source close to the production defended it, saying that Ukip "have to be a grown-up political party".

The source told the Guardian that Ukip should not expect blanket positive coverage.

"The idea that you have to be even-handed in a fictional piece is ridiculous. You have to look at Channel 4’s coverage in the round.

"Gogglebox did a piece with Nigel Farage which was extremely pro-Ukip, it was essentially a platform for Farage. He was allowed to have his pint and a chat," they said.

On Twitter the programme was the subject of derision, with many questioning why it had been commissioned in the first place. Producers of the programme were reportedly surprised at the reaction.

Others suggested that Ukip supporters had just reacted negatively to a show that mocked them.