LONDON (Reuters) – British banks or companies working with any aspect of Russian President Vladimir Putin’s administration should think carefully about whether their actions are propping up his “regime”, a spokesman for Prime Minister Boris Johnson said on Monday. Energy company BP and global bank HSBC were among a number of Western companies looking to exit Russia after Putin invaded Ukraine. “I think the prime minister’s view is that Putin’s regime and Putin must be treated like a pariah state and that businesses should think very carefully if they are still continuing to do anything that pr…