Rio Olympics officials have closed the diving pool in an attempt to speed up treatment of its green water.

While competition is expected to continue on schedule, training was stopped on Friday to allow for the water to remain still, a move designed to  help remove the persistent algae problem.

Officials maintain the water poses no risk to athletes, despite emerging reports that it was also giving off a foul smell.

German diver Stephan Feck posted on his Facebook account a photo of himself near the pool, holding his nose.

An inspector takes a sample. Photo: AP

The caption says: “The moment you want to do some workout and the pool is closed. The whole venue smells like somebody has fart[ed].”

Rio communications director Mario Andrada said the problem with the water’s colour had gone on longer than expected.

“We have learned that chemistry is not an exact science,” he said.

“We need to have the water stew so we can clean it faster and easier.”

Andrada also confirmed that initial efforts to fix the problem resulted in too much chlorine being added, which led to some athletes complaining of itchy or sore eyes.

International swimming body FINA said it supported the decision to stop training and that competition, a preliminary round for the women’s three-metre springboard, would start on schedule.

It said athletes would be able to use dry-training facilities until the pool reopened.