(Adds details on further expansion, context) Nov 29 (Reuters) -...

(Adds details on further expansion, context)

Nov 29 (Reuters) - World No. 2 iron ore miner Rio Tinto (RIO) gave the long-awaited green light for a $2.6 billion iron ore mine in Western Australia, with first production expected within three years.

The mine would have an annual capacity of 43 million tonnes, which is expected to underpin Rio's production of its flagship Pilbara Blend iron ore, it said in a statement.

The cost is higher than the $2.2 billion the company flagged last year. Rio Tinto on Thursday said the scope of the project had been broadened to include safety improvements, as well as additional infrastructure such as an airport and site access roads.

The miner added that it was mulling a second phase to expand annual production to more than 70 million tonnes, depending on the results of a $44 million pre-feasibility study in the region.

Rio expects to employ over 2,000 people during the construction of the project, with 600 permanent roles created upon completion.

Rio said the operation is designed to use increased automation - including autonomous trucks, trains and drills - and is expected to be its lowest cost contributor to its Pilbara blend product.