Thailand's constitutional court has ruled that a February 2 election opposed by anti-government protesters can legally be delayed.
The court said on Friday that the power for postponement rests with the prime minister in consultation with the Election Commission chief.
It said delays were justified under the law "to prevent public disaster and severe damage from happening to the nation or the people".
There was no immediate word on whether the vote called by Yingluck Shinawatra, the prime minister, would be postponed.
The head of the country's election body, which asked the court for the ruling, has argued that the polls should be delayed because of unrest that has shaken the country since protesters took to the streets late last year.
Yingluck's government had maintained that the date, fixed by royal decree, was unchangeable.
She called the election in the hope of confirming her hold on power in the face of protests trying to force her from office.
Varathep Rattanakorn, caretaker deputy prime minister, has said the government will have to study the ruling before deciding what action to take.
However, the protesters have already declared that an election postponement alone will not end their confrontation with Yingluck's caretaker government.
Suthep Thaugsuban, the protest leader, has demanded that Yingluck resign and that a non-elected council of "good people" govern and implement political reforms for up to two years before any ballot is held.
The protesters said Yingluck's government is carrying on the practices of Thaksin Shinawatra, her billionaire brother who was prime minister from 2001 to 2006.
They regard Yingluck as a stand-in for Thaksin, who was toppled by a military coup after street protests accused him of corruption and abuse of power. He fled into exile in 2008 to avoid a two-year prison sentence for conflict of interest.
The protesters have occupied key intersections in the capital and tried to shut down government offices and prevent civil servants from working to pressure Yingluck to resign. Unrest since November has left at least nine people dead and more than 550 injured.
The government this past week imposed a state of emergency on Bangkok and surrounding areas after a spate of violence.
The measure allows suspension of many civil liberties. The protesters said they will ignore any measures imposed by the decree, which is valid for 60 days.
Authorities announced Friday they are banning the protesters from 26 roads, and Suthep said his group would make a point of marching on all of them.
The opposition Democrat Party, which is closely allied with the protesters, is boycotting the election.
Chavanond Intarakomalyasut, Democrat Party spokesman, applauded Friday's ruling and urged the government to postpone the polls.
However, he said his party would only participate if it feels they are being held under trustworthy conditions.
Even if the vote goes ahead, parliament is unlikely to achieve the quorum it requires to convene because protesters have blocked candidate registration in several provinces.
That means a caretaker government would remain in place until at least some of those provinces hold elections.
Thailand has struggled with political tension off and on since the 2006 coup.