JERUSALEM, Dec 23 (Reuters) - Israeli Prime Minister Ehud Olmert and Palestinian President Mahmoud Abbas reached agreement on a number of issues during their first formal meeting on Saturday, an Abbas aide said. "This is the beginning of a series of meetings. It was a good meeting. There was agreement on several issues," aide Nabil Abu Rdainah told Reuters after the two-hour meeting in Jerusalem finished. Abu Rdainah did not elaborate.