Talks to resolve the conflict over Western Sahara should take place on the sole basis of a Moroccan plan that would give the region some autonomy under the North African kingdom's sovereignty, the Trump administration said on Tuesday.

Secretary of State Marco Rubio set out the U.S. position in a meeting with Moroccan Foreign Minister Nasser Bourita in Washington, making clear that President Donald Trump's 2020 move to recognise Moroccan sovereignty over the region remains U.S. policy, State Department spokesperson Tammy Bruce said in a statement.

"The Secretary reaffirmed President Trump's urging for the parties to engage in discussions without delay, using Morocco's Autonomy Proposal as the only framework, to negotiate a mutually acceptable solution," Bruce said.

The long-frozen conflict, dating back to 1975, pits Morocco, which considers the territory as its own, against the Algeria-backed Polisario front, which seeks an independent state called the Sahrawi Republic in Western Sahara.

Rubio said on Tuesday a proposal first put forward in 2007 by Morocco was "serious, credible, and realistic" and "the only basis for a just and lasting solution to the dispute," according to Bruce.

"The United States continues to believe that genuine autonomy under Moroccan sovereignty is the only feasible solution," she added.

Trump at the end of his first term in office recognized Moroccan claims to Western Sahara as part of a deal under which Morocco agreed to normalize its relations with Israel. Trump's successor Joe Biden shunned making a statement on Trump's move, leaving the U.S. position ambiguous.

The U.S. move to recognize Moroccan sovereignty over Western Sahara in late 2020 was followed by a similar decision by France in July last year.

Spain, the former colonial power in Western Sahara, said in 2022 that it backed Morocco's autonomy plan.

A U.N.-led process on the conflict has stalled with Morocco saying autonomy is the only basis for talks, while Polisario and Algeria insist on a referendum.

Morocco has also said that no talks are possible without Algeria's participation. Algeria, which has recognized the self-declared Sahrawi Republic, has refused to take part in roundtables convened by the U.N. envoy to Western Sahara and insists on holding a referendum with independence as an option.