JERUSALEM — Israel’s Supreme Court on Tuesday ordered the government to remove the largest unauthorized settlement outpost in the West Bank, one of scores built by settlers without official approval across the Israeli-occupied territory.

It was the first time that the court had ordered the evacuation of one of the wildcat outposts, which have spread across West Bank hilltops since the 1990s, sometimes as offshoots of established settlements that were built with government approval.

Although Israeli authorities have removed some of the outposts, most remain in place and many have government-funded access roads, electricity and water hookups.

The court ruled on the case of Migron, a cluster of about 60 mobile homes on private Palestinian land on a hill north of Jerusalem and considered the flagship of the unauthorized outposts. Palestinian landowners and the Israeli anti-settlement group Peace Now had petitioned the court in 2006, seeking the removal of Migron on the grounds that it was built illegally.

“There is no doubt that according to the law a settlement cannot be built on land privately owned by Palestinians,” Dorit Beinisch, president of Supreme Court, wrote in the ruling by a three-judge panel.

Noting that efforts to negotiate a voluntary move by the 300 settlers at Migron to a neighboring settlement had dragged on for nearly three years without success, the court ordered the government to remove the outpost by the end of March. The judges said there was no justification for further violation of the law and of the landowners’ rights to their property.

Michael Sfard, the attorney for the petitioners, said he was “extremely sad that in 2011 there is need for long and tedious litigation to compel the state to protect Palestinian private property.”

According to figures compiled by Peace Now, there are 99 unauthorized outposts in the West Bank, 80 of which are built wholly or partially on private Palestinian land. There are 120 established Israeli settlements in the West Bank, housing some 300,000 settlers. Much of the world regards the settlements as illegal under international law.