Egyptian authorities have begun building a wall near Rafah in southern Gaza, The New York Times reported.
Satellite images show bulldozers clearing a large area of land in the buffer zone. Work began around 5 February.
The contractor and engineer reported that they were commissioned by the Egyptian army to build a five-metre-high concrete wall to cover an area of 5 square kilometres. It is not yet known whether the structure is intended to contain Gazans.
A government spokesman declined to comment and referred to statements made by the authorities about fortifying the border.
Recall that Egypt threatened Israel with the breakup of the peace treaty.