"President Asif Ali Zardari and former Prime Minister Nawaz Sharif, in a bid to prolong their rule at the Centre and in the province of Punjab, respectively, are following American policies and have turned Pakistan into a US colony," he said.
Khan, who recently offered to broker a truce between the local Taliban and the government, claimed that if his Pakistan Tehrik-e-Insaf party is voted to power, it would transform Pakistan into a "true Islamic welfare state".
His party is considered close to the radical Jamaat-e-Islami and both parties boycotted the 2008 general election.
"My party is struggling to change the system and it will never join hands with opportunist political forces of the country," Khan said.
He said instead of torturing "small time thieves", the government should bring to book the beneficiaries of now-defunct National Reconciliation Ordinance (NRO), a graft amnesty that benefited Zardari and several of his close associates.
"The office of president is still in the clutches of a dictator, who is facing a friendly opposition in the form of the PML-N, and the political dispensation is similar to that of Gen Pervez Musharraf's regime," he added.
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