Egyptian President Abdel Fattah al-Sisi said on Tuesday that the escalation in Gaza was “highly dangerous” and that Egypt was pursuing a negotiated solution to the violence with regional and international partners.

Egypt would not allow the issue to be settled at the expense of others, Sisi said in comments reported by state news agency MENA, an apparent reference to the risk that Palestinians could be pushed into Sinai.

The Rafah border crossing remained shut on Wednesday morning, after Egyptian military planes conducted flights nearby overnight, security sources said. The military has also taken up new positions close to the border, running patrols to monitor the area, said Ahmed Salem of the Sinai Foundation for Human Rights.

Rafah is the sole possible crossing point into Sinai for Gaza’s 2.3 million residents. The rest of the densely populated strip is surrounded by the sea, and by Israel, which has announced a total siege of Gaza and could launch a ground offensive.

The passage of people and goods in and out of Gaza is strictly controlled under a blockade enforced by Egypt and Israel.

On Tuesday, the Israeli military revised a recommendation by one of its spokespeople that Palestinians fleeing its air strikes in Gaza head to Egypt.

Israel has been pounding Gaza with the fiercest strikes in the 75-year history of its conflict with the Palestinians since Hamas launched a deadly incursion into Israel on Saturday.