Tehrik-e-Insaf Chief Imran Khan reacted sceptically on Saturday to Islamabad's apparent crackdown on al Qaeda, saying the government was desperate for the support of the United States.
"Just because the government calls someone al Qaeda, doesn't mean they are al Qaeda, because the government is desperate for American support," Khan told BBC radio.
"We don't know who is al Qaeda or who is who," he said.
"The problem is that people are abducted in Pakistan, they are not presented in a court of law, they are not allowed to prove their innocence, there are so many people that have disappeared," he said.
Imran warned that President Pervez Musharraf's administration was too dependent on US support.
"Our government is no different to the Iraqi governing council," he said.
He also said political power in Pakistan was dangerously concentrated in one person, the president.
"The real power is with General Musharraf," Khan said.
"The whole system depends on one man. And he has narrowly escaped a suicide attack against him. If anything happens to him, there is chaos ahead.
"What should have happened in Pakistan is that we should have had a genuine democracy which should have dealt with this issue."
He said that Pakistanis as a whole were also deeply sceptical about Islamabad's support for the so-called war on terrorism.