BG Group reported Thursday that it has started commercial gas production from the second phase of its Itaú development in Bolivia. The firm said the start-up of gas production makes the "final key milestone" for the group in 2013.

With first production from Itaú Phase II, BG Group said that it has delivered its promise to bring into production new oil and gas projects in Brazil, the UK, Thailand and Bolivia and to complete large planned maintenance campaigns on core assets in Kazakhstan and the UK.

The production start-up of Itaú at follows BG Group's announcement Monday of another major project milestone in Australia, with first gas transported onto Curtis Island, the site for the Queensland Curtis LNG project's liquefaction plant.

Commenting on the news, BG Group Chief Executive Chris Finlayson said in a company statement:

"In February we set clear yet challenging milestones for the year as we focused on safety and excellence in execution. With first commercial production from Itaú Phase II we have now delivered all the milestones we promised, the product of hard work and dedication by the people working across our business. We have achieved what we set out to do, and importantly we have done it safely."