At least 20 Palestinians were killed on Friday in an Israeli airstrike in Gaza, according to local health officials, as U.S. President Donald Trump said he expected Hamas to respond to his "final proposal" for a ceasefire in Gaza in the next 24 hours.

More than 60 of those killed were waiting for aid, according to Palestinian health officials. President Trump said Friday that talks over a ceasefire between Israel and Hamas are at a crucial stage.

Dr Marwan Sultan was killed along with several family members in a strike on his home, the health ministry says.