The US has released previously unseen documents about the 1979 Camp David peace deal between Egypt and Israel, which were brokered by Washington.
The Security of State made the announcement in a statement on Thursday.
"This added material consists largely of personal handwritten notes taken at the September Camp David summit by Samuel W. Lewis, the US Ambassador to Israel," the statement said.
"Department of State historians found these notes while researching volumes for the administration of President Ronald Reagan," it added.
Among the findings were that Egypt feared being isolated from its neighbours, if Israel did not fulfill its promises.
A letter by the-then Egyptian Prime Minister Moustafa Khalil said that Israel's expansion into the occupied Palestinian terriories
The US published the first part of the secret documents in 2014.
The Camp David peace accords were signed between Egypt and Israel in September 1978 leading to the peace treaty the following year.
It signalled the end of hostilities between the two countries, but it was never fully embraced by a sceptical Egyptian public.