130 community groups will attend a summit in Aylesbury later on the government's plans to build a high speed railway line through the Thames Valley.
15 local authorities from across the South have launched a legal challenge to plans to build the £32 million pound line from London to Birmingham.
The government believes that HS2 is necessary to improve the UK's infrastructure and the economic prospects of the North of England.
The Lord Lieutenant of Buckinghamshire will chair the summit which will focus on the environmental impact of the project.
Alison Munro the CEO of HS2 Ltd is expected to attend.
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Cloud and rain first thing but it will gradually dry up from the north west. Becoming bright in the west, staying quite cloudy in the east
Rain becoming more persistent overnight. Rain and cloud slow to clear tomorrow but becoming dry by the afternoon. Some brightness later