Pakistan has failed to send a team of officials to India to investigate the November 2008 Mumbai (Bombay) attacks, Indian officials said.
Islamabad told Delhi that the judicial commission would not be able to come as planned, a home ministry official said.
The team was due to arrive in Mumbai on Thursday. Its members were due to meet Indian officials and doctors involved in the investigation.
The Mumbai attacks claimed 165 lives. Nine gunmen were also killed.
The sole surviving gunman from the attacks, Mohammad Ajmal Amir Qasab, was convicted of murder and waging war on India in May 2010 and given a death sentence.
His appeal is pending in the Supreme Court.
Officials said no reason had been given for the cancellation of the visit.
Pakistan had agreed last year to send a judicial team to India during home secretary-level talks between the two countries.
The 60-hour siege of Mumbai began on 26 November 2008, targeting luxury hotels, the main railway station and a Jewish cultural centre.
Relations between India and Pakistan hit rock bottom after India blamed Pakistan-based militant group Lashkar-e-Taiba for the attacks.
After initial denials, Pakistan acknowledged that the assault had been partially planned on its territory and that Qasab was a Pakistani citizen.
Islamabad told Delhi that the judicial commission would not be able to come as planned, a home ministry official said.
The team was due to arrive in Mumbai on Thursday. Its members were due to meet Indian officials and doctors involved in the investigation.
The Mumbai attacks claimed 165 lives. Nine gunmen were also killed.
The sole surviving gunman from the attacks, Mohammad Ajmal Amir Qasab, was convicted of murder and waging war on India in May 2010 and given a death sentence.
His appeal is pending in the Supreme Court.
Officials said no reason had been given for the cancellation of the visit.
Pakistan had agreed last year to send a judicial team to India during home secretary-level talks between the two countries.
The 60-hour siege of Mumbai began on 26 November 2008, targeting luxury hotels, the main railway station and a Jewish cultural centre.
Relations between India and Pakistan hit rock bottom after India blamed Pakistan-based militant group Lashkar-e-Taiba for the attacks.
After initial denials, Pakistan acknowledged that the assault had been partially planned on its territory and that Qasab was a Pakistani citizen.