By Louis Charbonneau UNITED NATIONS, Aug 22 (Reuters) - Britain, France and Germany have floated the idea of creating a monitoring and verification mechanism for any future ceasefire between Israel and the Palestinians in the Gaza Strip to prevent future conflicts, a senior British diplomat said on Friday. The proposal was contained in an outline for a possible draft resolution prepared by the three European powers. U.N. Security Council diplomats said on condition of a**nymity that the trio is discussing the proposal with several of the 15 council members, including the United States and Jordan, as well as **n-council members Israel and Egypt.