Islamabad: Muslim Milli League (MML) was denied permission to register as a political party just weeks before national polls, officials said.
The MML was launched last August to contest the July 25 elections, which will be only the second democratic transfer of power in Pakistan´s history.
But the group was blacklisted by the US in April as Washington ramped up pressure on Islamabad to crack down on extremist groups operating in the country.
On Wednesday the Election Commission officially rejected their application to register as a political party.
"The Election Commission of Pakistan today rejected the registration request by the Milli Muslim League as a political party," spokesman Altaf Ahmad told AFP.
He said that a detailed order would be issued later stating the reasons for the commission´s decision.
The MML was founded by charity Jamaat-ud-Dawa (JuD).
In a press statement, MML spokesman said that his party would challenge the ECP's verdict in superior courts .