The 30,000-square-foot crib, which has been dubbed the "Starship Enterprise" -- it's that big -- is unsafe for a of myriad reasons, according to the judge who ruled this week in L.A. Superior Court. In the judge's words, the mansion is a "clear and present" danger to Mohamed's neighbors.

The concern Hadid's neighbors and the city have had for years is that it's on an unstable hillside and wasn't constructed up to safety standards. The judge affirmed that in court, saying, "If this house came down the hill it would take a portion of the neighborhood with it."

A structural engineer told the court the supporting piles under the home were only driven 20 feet into the bedrock, instead of the 30 feet required by regulations. Hadid had hoped to sell the mansion for 9 figures.

Mohamed's neighbors had sued him over the construction and scored a huge victory with the judge's ruling. Demolition for the home will cost an estimated $5 million, and the judge has turned that responsibility over to a receiver named Douglas Wilson.

The judge is ordering Mohamed to pay Wilson a $500k fee, but Mohammed tells us his LLC's financing is strictly for construction, NOT demolition.

As for the judge saying the house is unsafe ... Mohamed says it "has not moved a millimeter! It has never been an imminent danger to the neighbors." He adds there were plenty of city inspectors who observed construction, which started in 2012, and he's pissed no one said anything until years later ... when he'd already spent millions.

Mohamed blames one particular neighbor, who he claims demanded $3.5 mil, or he'd report building code violations to the city. Mohamed sued him for attempted extortion, and tells us that suit is still pending.