RT has been fined £200,000 by the media regulator for breaching impartiality rules.

The Kremlin-funded news channel, formerly known as Russia Today, was found to have broken the British broadcasting code on seven occasions in the six weeks after last year’s Salisbury novichok poisoning. Despite the fine it will be allowed to retain its licence and continue broadcasting in the UK.

“Taken together, these breaches represented serious and repeated failures of compliance with our rules,” said Ofcom. “We were particularly concerned by the frequency of RT’s rule-breaking over a relatively short period of time.”

The serious breaches of the code meant the regulator had a number of ways of punishing RT, including revoking its licence to broadcast in the UK. Instead, the regulator concluded it was more just to impose a substantial fine and require RT to broadcast a summary of the findings, in a form and on dates to be determined by Ofcom.

Ofcom said this was fair since “we have not recorded any further breaches of our due impartiality rules against RT to date”.

The channel will not have to pay the fine and broadcast Ofcom’s ruling immediately, since it is challenging the initial ruling through a judicial review. The case is expected to reach the courts by the end of the year.

The Russian government has retaliated against Ofcom’s actions by launching investigations into the BBC’s Russian service, sparking a diplomatic media war.

Politicians had raised concerns about the tone of RT’s output in the aftermath of the Salisbury incident, although Ofcom has previously said this did not influence its decision to put the station under additional monitoring.

In total, Ofcom investigated 10 RT programmes broadcast between March and May last year, concluding that seven breached rules on due impartiality regarding matters of political controversy.

Two of the breaches related to programmes hosted by the former MP George Galloway, a regular presenter on the channel, who cast doubt on the link between the Salisbury poisonings and Russia. He has since lost a job at TalkRadio, after he was the subject of a negative Ofcom ruling at that broadcaster regarding his comments on the incident.

Other RT breaches include incidents in which presenters failed to challenge interviewees over contentious topics and instead appeared to agree with their guest, and programmes and reports about the conflict in Syria that took a resolutely pro-Russian viewpoint without representing alternative views.

RT has previously argued it did not breach rules of due impartiality, partly since its viewers expect to see a pro-Russian viewpoint when they tune in to the station.

A spokesperson for the channel said they find “the scale of proposed penalty to be particularly inappropriate and disproportionate per Ofcom’s own track record”.

“It is notable that cases that involved hate speech and incitement to violence have been subject to substantially lower fines. It is astonishing that, in contrast, Ofcom sees RT’s programmes – which it thought should have presented more alternative points of view – as worthy of greater sanction than programmes containing hate speech and incitement to violence.”

Despite the substantial media attention given to RT’s output, its British station has a relatively small reach of 332,000 viewers a week, despite being available to most households on Freeview, fewer than pay-TV channels such as Horror Channel +1, Kerrang TV, and Total Country.