Top officials urge dialogue with Hamas - The Boston Globe
The group includes Brent Scowcroft, Lee Hamilton and Sam Nunn is organized by Henry Siegman in the US/Middle East Project.
This 2007 post is also relevant.
Meantime, Britain has reverted to its prior policy vis-a-vis Hezbollah, namely to distinguish between the political and military wings of the Lebanese party and to resume "selective contacts" (informal contacts have been underway for the past two years). Jeffrey Feltman, the acting and presumptive Assistant Secretary for the Near East was probably the "senior official" who invited the UK to explain “the difference between the political, military and social wings of Hezbollah because we don't see a difference between the integrated leadership that they see”. The Foreign Office calculates that through "selective contacts" it may encourage Hezbollah's constructive political integration into the Lebanese political system.