MANCHESTER, England, Oct 3 (Reuters) - The availability of fuel at petrol stations across most of Britain has improved but there is still a problem in London and the South East, the chairman of Prime Minister Boris Johnson"s governing Conservative Party said on Sunday. "There is clearly a problem still in London and the South East and people feel deeply frustrated, and I share their anger and frustration at not being able to get access to petrol. That"s why the government is working tirelessly to resolve that situation," Oliver Dowden told Sky News.