In the first very admission of technical glitches in the Kudankulam atomic power plant, the Atomic Energy Regulatory Board (AERB) on Friday confirmed that regulators had found four faulty valves at the reactor.

The AERB said the four faulty valves were detected during a series of testing of thousands of valves in the Unit-1 ahead of its commissioning.

The atomic power regulator said in a statement, "During testing of thousands of valves installed in the plant, the performance of four valves of a particular type was found deficient."

However, it didn't specify the precise nature of the deficiency in the four valves in the plant's Unit-1, which is being developed with Russian help.

The task of replacing the faulty valves is being performed by the Nuclear Power Corporation of India (NPCI). Their performance will then be reviewed by the AERB.

The regulatory board said it would give the subsequent clearances only after conducting a satisfactory review.

This is the first time that the AERB has admitted to a technical glitch in the two 1000-MW reactors of the Kundankulam atomic power plant, which has been suffering excessive delays in becoming operational. It was originally scheduled to become operational in December 2011.