The humanitarian summit has started. For the latest, we cross live our correspondent Michal Bardavid in Istanbul.

Q1. The gathering was conceived four years ago by UN Secretary General Ban Ki-moon. The UN says it consulted 2,300 people in over 150 countries, Pls tell more details of the agenda and  what outcomes can we expect from this summit?

Q2. There has been criticism that its actual outcomes could fall well short of its lofty ambitions. What challenges ahead for participants to reach practical deals?