DHAKA, Oct. 7 (Xinhua) -- Bangladesh's apex court on Sunday dismissed the review petition filed by a death row convict in the murder case of Saudi diplomat Khalaf Al Ali.

A four-member bench of the Appellate Division of the Supreme Court (SC) headed by Chief Justice Syed Mahmud Hossain made the ruling, clearing the way for the execution of Saiful Islam Mamun Mamun who is now behind the bar.

The SC in November last year upheld the death sentence for Mamun and life terms for three others in the murder case of Saudi diplomat Khalaf Al Ali.

According to sources, the death row inmate is now left with the only option of seeking presidential clemency.

If the president rejects his pleas, the government will fix a date and prison authorities will start the process to execute the verdict.

Khalaf, 45, a second secretary at the Saudi embassy in Dhaka, was shot dead near his Gulshan house in Dhaka's diplomatic enclave in the wee hours of March 6, 2012.

Belying speculations about third-party role, Bangladesh police announced that Saudi diplomat's murder was related to street crime.

This is the first time a foreign diplomat was murdered in Bangladesh.