By Andreas Rinke BERLIN (Reuters) - Leaders of Chancellor Angela Merkel's German conservatives largely support Greece's new bailout plan before a parliamentary vote this week, but top party officials want the IMF to take part, sources involved in party talks on Monday said. A German Finance Ministry official also described involvement by the International Monetary Fund as "indispensable" and German EU Commissioner Guenter Oettinger said: "We still need it". The Bundestag is due to vote on the aid package on Wednesday and, while it is expected to be approved, many of Merkel's conservatives may break ranks and reject the 86 billion euro ($95 billion) programme.