JERUSALEM — A pair of Israeli rights groups on Wednesday asked the country’s Supreme Court to overturn a new law legalizing dozens of settler outposts in the West Bank, opening what is expected to be a long battle over the legislation, which has drawn international condemnation and been questioned by Israel’s own attorney general.

The law, backed by Prime Minister Benjamin Netanyahu’s nationalist coalition, retroactively legalized thousands of homes built on private Palestinian land. Its backers claim the homes were built ‘‘in good faith’’; critics say the law amounts to land theft.

The Arab rights group Adalah and the Jerusalem Legal Aid and Human Rights Center asked the high court to block the law. It was the first in what is expected to be a series of legal challenges.

‘‘This sweeping and dangerous law permits the expropriation of vast tracts of private Palestinian land, giving absolute preference to the political interests of Israel,’’ said Suhad Bishara, an attorney for Adalah. She said the court gave Israel 30 days to respond.

In the meantime, the state can begin implementing the law. Experts say the process will take years to identify properties, confiscate lands, and work out compensation with the original owners.

The West Bank is home to some 120 settlements recognized by Israel and 100 unauthorized outposts the government has tacitly accepted. The new law sets out a process to legalize about half of those outposts, as well as 3,000 more homes built illegally.