LONDON: The UK government on Monday expressed regret over reports that the Indian flag was burnt during a demonstration by separatist groups outside the Indian high commission in London on Republic Day The Foreign and Commonwealth Office (FCO) said it was disappointed that separatist groups had chosen to take such an action, as Scotland Yard confirmed that it was working to establish the exact circumstances around the incident on Saturday."We are disappointed that anyone would chose to burn the Indian flag on any day, let alone the celebration of Republic Day, and we regret the upset that this will have caused," an FCO spokesperson said."We congratulate India on Republic Day celebration, and look forward to deepening our relationship further as we prepare to leave the European Union and forge new partnerships with key global allies," the spokesperson added.A small group of activists from some British Sikh and Kashmiri outfits had gathered outside India House in central London on Saturday to wave placards against Prime Minister Narendra Modi and chant anti-India slogans. Indian officials had confirmed that the Metropolitan Police had been made aware of the planned demonstration, during which some protesters were caught on camera burning the Indian flag."On Saturday, 26 January a demonstration took place outside India House in Aldwych, WC2. An appropriate policing plan was in place," the Metropolitan Police said in a statement."There were no incidents of note and no arrests. No allegations of crime have been reported. We are aware of a social media video that appears to be from the demonstration outside India House in Aldwych on Saturday, 26 January. We are working to establish the exact circumstances of it," the statement said.The FCO had earlier called on demonstrators to stay within the law in reference to reports of a planned protest to mark Republic Day."We are proud to be a country that fiercely protects the rights of individuals to peaceful protest and free speech as essential parts of a vibrant democracy, provided that demonstrators act within the law. We do not condone the burning of national flags, which is deeply offensive to most people," an FCO spokesperson had said.In April last year, the Indian government had demanded legal action against those behind a similar desecration of the Indian flag at Parliament Square on the sidelines of the Commonwealth Heads of Government Meeting (CHOGM) in London attended by the Indian prime minister.The perpetrators, caught on camera with the Indian tricolour, were pro-Khalistani demonstrators brought together with Kashmiri separatist groups under the banner of a so-called "Minorities Against Modi" group. Similar groups are believed to be behind the latest incident outside India House in London on Saturday.