"Work mechanisms and double-standards on the Security Council prevent it from carrying out its duties and assuming its responsibilities in keeping world peace," the foreign ministry said.
"Therefore Saudi Arabia... Has no other option but to turn down Security Council membership until it is reformed and given the means to accomplish its duties and assume its responsibilities in preserving the world's peace and security," a statement said.
For the first time ever, oil-rich, conservative Saudi Arabia won a seat yesterday on the 15-member council, which has a key role in dealing with world conflicts.
But the foreign ministry said Saudi Arabia declines to be a member of a body unable to tackle long-standing conflicts in the Middle East or rid the region of the threat of nuclear war.
Also Read
It pointed specifically to the nearly three-year civil war in Syria and the protracted Palestinian-Israeli conflict, as key reasons.
"Failing to find a solution to the Palestinian cause for 65 years" it said, has led to "numerous wars that have threatened world peace."
The ministry also criticised the body's "failure" to turn the Middle East into a region free from weapons of mass destruction, including nuclear arms -- in a reference to Iran and Israel.