Abbas should clarify that, other than themselves, these meetings should also be attended by one representative 'observer' each from Israel, the PA, the US, the EU, the Arab League, and the UN(one from Hamas would be the ideal, but....?). And bottom line, THIS should be something that's insisted on for the whole process. NOT to be directly involved in the talks, but to act as independent witnesses and serve as liaisons - POC's for information, assistance, etc - to and for the entities they represent.
Germany shelves Nazi crimes probe of US national Karkoc (AP)
from the article: Report: Palestinians reject bid for bi-weekly Netanyahu-Abbas meetings