Pro-reservation parties on Thursday attacked the Supreme Court judgment staying reservation for backward classes in elite educational institutions and sought Parliament's 'intervention' while the government made it clear that Parliament will stick to the law.

Tamil Nadu Chief Minister M Karunanidhi, whose state is a pioneer in the affirmative action and has reservations up to 74 per cent, expressed shock over the judgment.

However, Congress and the Bharatiya Janata Party were ambiguous and not forthcoming in their reactions while anti-reservation outfits hailed the order staying the recent central law providing for 27 per cent reservation for backward classes in IITs, IIMs and central universities.

UPA partner Communist Party of India came out with the strongest reaction calling the judgment 'retrograde,' which it said would not help in implementation of policies to ensure social justice and equality.

It said the government should have intervened even when the apex court questioned the ninth schedule of the Constitution.

"Parliament has to intervene effectively. Time has come for Parliament to have an effective say on this. It cannot be left to the judiciary," party national secretary D Raja said.

The Communist Party of India-Marxist also had strong words on the judgment with party general secretary Prakash Karat calling it 'unfortunate and uncalled for.'

He said that already several states had implemented reservation on the basis of OBC lists even in Central services and wondered what the problem in extending it to educational institutions was.

"We want the Central government to take necessary steps in Parliament to ensure the implementation of the law," he said.

The party's Polit Bureau also issued a statement saying the 27 per cent reservation for OBCs in government jobs was decided on the basis of the Mandal Commission report and the Supreme Court had upheld the quota along with the exclusion of the creamy layer.

The party said the judgment has ignored the fact that there are clear-cut lists of backward classes in all the states on the basis of which reservation for them was there in educational institutions in many states.

In his reaction, Union Human Resources Development Minister Arjun Singh, considered the brainchild of the concept, said the principle of legislation has been accepted by Parliament and the Constitution amendment has already been carried out unanimously.

"Parliament will stick to it. There are legal objections. We will try to meet them," he said.

Shortly after the court's order, Singh put up a brave face saying it was not a setback to the government and said the Centre will take all 'constitutional and legal steps to ensure that the law is valid.'

After a cabinet meeting, Parliamentary Affairs Minister Priyaranjan Das Munshi said the Law Ministry will study the order and then the Government will take a decision. The matter did not come up in the Cabinet meeting, he added.

The ruling Congress said it was an interim arrangement till the next hearing, while the Opposition BJP used the opportunity to slam the government for its 'abject failure to project the case of social backwardness in the right perspective.'

Karunanidhi said the next course of action would be decided in consultation with leaders of political parties and social organisations interested in providing reservation to backward classes.

Former prime minister V P Singh, who was responsible for the implementation for backward classes in central services, sought implementation of the law providing for reservation for them in educational institutions, while a fresh census can be made to ascertain the number of people belonging to backward classes.

Indian Justice Party chief Udit Raj said he deplored the judgement which he felt was 'meddling' with the law passed by Parliament.