The court's decision came on a petition filed by social activist Gorakh Prasad.
On June 24, the state government had directed District Magistrates and Commissioners to issue Scheduled Caste certificates to 17 OBCs - Kashyap, Rajbhar, Dhivar, Bind, Kumhar, Kahar, Kewat, Nishad, Bhar, Mallah, Prajapati, Dhimar, Batham, Turha, Godia, Manjhi and Machua.
The government's move was apparently aimed at wooing these communities ahead of by-elections to 12 Assembly seats.
The decision, incidentally, had been criticized even by the BJP-led Central government, with Social Justice and Empowerment Minister Thawar Chand Gehlot telling the Rajya Sabha on July 2 that the move was not in accordance with the Constitution.
Gehlot had said that if the UP government wanted to go ahead with its proposal, it should follow procedure and send a proposal to the Centre.
BSP chief Mayawati had also slammed the move as "unconstitutional" and called it "politically motivated".
"No government can include or remove any caste from the Scheduled Caste list. Article 341 prevents a government from doing so. Only the President and Parliament have the powers to do so," she had said.
Part 1 of Article 341 clearly states that the President can specify any group to the SC list through a public notification on the Governor's advice. Part 2 says that if a notification is released under part 1 of Article 341, it can only be changed by Parliament. Part 2 also states that Parliament can specify, include or exclude any group from the SC list.
She pointed out that the notification cannot be undone by any other notification.
"These castes will no longer get the benefits of quota under the OBC category. They will be treated as general castes. It is clear that Yogi government has issued this order to deceive these castes," Mayawati had said.
The BJP government in Uttar Pradesh is not the first to move the 17 OBCs to the SC list.
In 2005, the then Mulayam Singh Yadav government passed the first order to include 11 of these castes in the SC list but the order was stayed and the proposal sent to the Centre.
Subsequently, the BSP government of Mayawati quashed the notification.
The BSP later said these castes could be included in the SC list provided the SC quota is increased.
The SP government of Akhilesh Yadav again cleared the inclusion proposal ahead of the 2017 assembly elections but it was challenged and is still in court.
( With inputs from IANS )