An 11-member delegation of opposition parties from Delhi, which wanted to visit Kashmir Valley to take stock of the situation there after the abrogation of Article 370 provisions, was not allowed to leave Srinagar airport by the administration on Saturday, the CPI(M) said.
The delegation representing eight political parties - the Congress, CPI(M), CPI, DMK, NCP, JD(S), RJD and the TMC -- had said that they were "responding to the invite of the governor of Jammu and Kashmir for visiting the state".
A statement from CPI(M)'s Politburo slammed the government over "denial of entry" into Srinagar to opposition leaders, alleging it was "daylight robbery of rights" guaranteed by the Constitution.
The development comes a day after the Jammu and Kashmir government issued a statement asking political leaders not to visit the Valley as it would disturb the gradual restoration of peace and normal life.
It also said the visit by politicians would be in violation of restrictions that have been imposed in many areas of the Valley.
The joint delegation of the opposition had flown to Srinagar around noon on Saturday to meet the people of Jammu and Kashmir and assess the situation there following the imposition of restrictions after the Centre withdrew special status to the state and bifurcated it into two Union Territories.
"The delegation had planned to visit various parts of the state over the next few days, talking to various people and sections of the populace and shades of political opinion to ascertain the situation existing on the ground and the difficulties that they are encountering as a result of the shutdown in the Kashmir valley for days together," the CPI(M) statement said.
"The denial of entry to well-known leaders of recognized political parties is an outright attack on the rights of political parties to meet and address their constituents," it said.
The CPI(M) also alleged misbehaviour of police with media at the airport.
"If 'normalcy' exists in the Valley as claimed by the government, why is it stopping representatives of political parties from meeting the people?" it asked
It said that the people of the country were watching this "blatant trampling upon of the democratic rights of people and their representatives by a party which seeks to impose a totalitarian regime".