The parliament said "the probe should not be carried out on the ground that such a course of action is detrimental to the process of reconciliation and peace."
The government of President Mahinda Rajapakse, which enjoys a two-thirds majority in the 225-member assembly, said the UN probe also "erodes the sovereignty, dignity and stature of Sri Lanka." President Rajapakse himself had earlier rejected the UN probe into charges that up to 40,000 ethnic Tamil civilians were killed by security forces while crushing Tamil separatists in May 2009.
Two opposition parties drawing their support from the majority Sinhalese community said they too would not support the UN inquiry, but insisted that Colombo set up a domestic process to probe the allegations.
The Sri Lankan parliament's rejection is not binding on the U