Calcutta, Sept. 2: The Election Commission of India today recognised the Trinamul Congress as a national party.

Trinamul has become the seventh party to get the tag after the Congress, BJP, BSP, CPM, CPI and the NCP.

Commission sources said this evening that in a recent review of the status of various political parties across the country, it was noted that Trinamul had satisfied the criteria for receiving the national tag - recognition as a state party in four states. Trinamul is recognised as a state party in Bengal, Manipur, Arunachal Pradesh and Tripura.

According to the Election Symbols (Reservation and Allotment) Order, 1968, a political outfit must fulfil any one of three criteria for recognition as a national party.

"Recognition as a national party ensures that its symbol cannot be used by anyone else in any election in India. It also makes the parties eligible for land or buildings from the Centre to set up party offices in the capital," said Biswanath Chakraborty, a professor of political science at Rabindra Bharati University.

National parties are allowed to have free airtime on public broadcasters and 40 "star campaigners" in elections. Such parties also get special exemptions under expenditure-monitoring rules.

In a tweet, chief minister Mamata Banerjee said: "Landed in Rome & got great news.... We started in Bengal 18 yrs ago & now being blessed by u across India."