An Indian convicted of burning a compatriot to death was beheaded in Aseer in southern Saudi Arabia on Saturday.
G Krishna allegedly burnt one Madrasa Iqbal to death while the latter was asleep following some quarrel.
The Saudi authorities do not inform the foreign missions ahead of the execution of expatriate convicts, according to Indian embassy sources.
This has made it difficult for embassies to keep track of or defend those accused of serious crimes, they added.
The execution brings the total number to nine this year in Saudi Arabia, one of the countries with worst human rights record.
In 2004, Saudi authorities executed 35 people. The year before the number was 52. Many are publicly beheaded.
As per Sharia rule, Saudi Arabia gives death to those convicted of murder, rape and drug trafficking.