(Adds analyst estimates of impact in paragraphs 5 and 6)...

(Adds analyst estimates of impact in paragraphs 5 and 6)

MELBOURNE, June 21 (Reuters) - The world's biggest iron ore miner Rio Tinto (RIO) said on Wednesday that it had reopened a rail line at its Western Australian operations after a train carrying iron ore near the port of Dampier derailed at the weekend.

The line will remain subject to speed restrictions while a clean up of the site is underway and an investigation into the cause of the derailment is ongoing, a Rio Tinto spokesman said via email.

The incident on Saturday was the second such event in recent years after peer BHP Group (BHP) derailed a runaway iron ore train in the same region in late 2018.

The loaded train with some 30 wagons would have been carrying around 3,900 to 4,500 metric tons of iron ore, according to one estimate.

Analysts expect Rio to have drawn from port stocks in the meantime, which could impact its ability to blend ore to meet customer requirements.

Rio Tinto has not said what the impact on its customers would be, if any, and declined any further comment.