GLASGOW, Nov 2 (Reuters) - British Prime Minister Boris Johnson said it was important to guard against false hope at the United Nations climate conference in Glasgow, but some progress had been made during the opening days. "We must take care to guard against false hope and not to think in any way that the job is done, because it is not - there is still a very long way to go," Johnson told a news conference. "But all that being said, I am cautiously optimistic."