Lawyers of Pakistan's former military ruler Pervez Musharraf on Friday called for an "immediate and unconditional" suspension of his treason trial, claiming the government is colluding with elements of the judiciary to "fix and manipulate" the proceedings.
In a statement issued in London, the lawyers alleged that Prime Minister Nawaz Sharif has "manipulated the Pakistani legal process and used unlawful influence on the...judiciary to bring a barrage of unsubstantiated charges" against Musharraf, his long-time political rival.
They called for an "immediate and unconditional suspension of the special court and a comprehensive investigation" into their claims.
The lawyers gave no specific details of their new claims, but said they had submitted them to the office of UN human rights chief Navi Pillay.
They have written to the UN urging it to intervene to stop what they call a "show trial", claiming Sharif has handpicked the three judges hearing the case.
Toby Cadman, an international human rights lawyer on Musharraf's team, said: "There is an obvious conflict of interest between the judiciary in charge of the former president's trial and the issue at stake.
"The recent disclosure demonstrates the level of collusion between the executive and the courts. The legal team said it based its claim on "leaked secret communication" from an unnamed source in the office of Prime Minister Sharif.
They also urged King Abdullah of Saudi Arabia to intervene and support Musharraf in return for the former president's role in developing "brotherly relations" between their countries.
Musharraf, 70, is the first military ruler in the Pakistan's history to face trial for treason charges for suspending and abrogating the Constitution and imposing an emergency in November 2007.
The case is viewed as a test of civilian authority over the powerful military.
Musharraf appeared in court on February 18, but since then has missed repeated hearings due to bomb scares and heart problems.
The special tribunal hearing the case last week ordered Musharraf to appear in person on March 31 or face arrest.