As U.S. President Barack Obama prepared to deliver a highly anticipated keynote speech at the University of Cairo, he called for patience and persistence.

"Diplomacy is always a matter of a long, hard slog," he told the BBC. "It's never a matter of quick results."

In the years since the 1967 Six-Day War, progress has been made — peace has been brokered between Israel and Egypt, as well as between Israel and Jordan. But despite several summits, peace accords and plans, lasting stability for the region remains elusive.

Here is a timeline of proposed peace accords from 1967 to 2007.

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