The decision comes after more than a year of escalating fighting between Sri Lankan government troops and the rebel Liberation Tigers of Tamil Eelam (LTTE) and the almost total collapse of the island's peace process.
"The government and the LTTE were informed about our decision on May 12," said Christine Berg of the Sri Lanka Monitoring Mission (SLMM).
"We, however, continue to entertain complaints from anybody, but we will not announce a ruling. In fact the last ruling was handed over way back in April," Berg told AFP.
The SLMM was put in place by peace broker Norway to monitor the ceasefire after both sides signed a truce in February 2002.
The ceasefire was meant to end the ethnic conflict that has claimed more than 60,000 lives on this island nation in the past 35 years.
But after temporarily halting the bloodshed for two years, the deal began to unravel.
More than 5,000 people have died, according to official figures, after both sides stepped up ground, sea and air att