Israeli invasions in Rafah, which started this month, have closed a main crossing point for aid from the border with Egypt, a move humanitarian groups say has worsened an already dire situation.
"Especially in the past few weeks, we have seen some momentum building but unfortunately, things didn't move in the right direction and right now we are in a status of almost a stalemate. Of course, what happened with Rafah sent us backward," Sheikh Mohammed said at an economic forum in Doha.
Israeli tanks forged deeper into eastern Rafah, reaching some residential districts, on Tuesday, stepping up an offensive in the city where more than a million people had been sheltering after being displaced in seven months of war.
Sheikh Mohammed, whose country has mediated heavily between Palestinian Islamist group Hamas and Israel throughout the seven-month conflict, said Qatar would keep working to resolve the situation.
"We make it very clear for everyone: our job is limited to our mediation," he said. "That's what we will do, that what we will continue to do."
Sheikh Mohammed said the fundamental difference between the two parties was over the release of hostages and ending the war.
More than 35,000 Palestinians have been killed in Israel’s assault on the Gaza Strip, say health officials in the Hamas-ruled enclave.
"There is one party that wants to end the war and then talk about the hostages and there is another party who wants the hostages and wants to continue the war. As long as there is not any commonality between those two things it won't get us to a result," Sheikh Mohammed said.
Sheikh Mohammed warned that even should the war stop, with no clear rescue plan for Gaza, there was a risk of growing radicalisation in the medium term.
"We are very much worried after all these images to see another wave of radicalisation. So security is the key for us in the region. We need to preserve it as much as possible."
MNA/PR