A reactor at a nuclear plant in western India was shut down Friday after a water leak was discovered, officials said, stressing that workers had not been exposed to radiation.

No radioactive material had leaked from the Kakrapar Atomic Power Station in the coastal state of Gujarat, the director of the site said.

"Consequent to a small leak in the primary heat transport system, the reactor was shut down as intended as per design provisions," L. K. Jain said in a statement.

"All safety systems are working as intended. The radioactivity/radiation levels in the plant premises and outside are normal."

The unit was shut down at about 9:00 am (0330 GMT) and would restart only after officials from India's Atomic Energy Regulatory Board inspect the plant and give it the go-ahead.

The plant's two reactors produce 440 megawatts of power, while two more are being built.

In 2011, four labourers at the plant were exposed to radiation when they were painting a tunnel. 

India's 20 nuclear plants currently account for less than two percent of its power capacity.

Although the government wants to boost this to 25 percent by 2050, concerns over radiation leaks and the effect on residents living near proposed sites have led to protests and stalling of major projects.

In 2014, six workers suffered nearly 50 percent burns at a Russian-backed plant in southern Tamil Nadu state.