The boss of Snowy Hydro has resigned amid reported cost blowouts and delays on the Snowy 2.0 project in the NSW Snowy Mountains.
Chief executive and managing director, Paul Broad, has led the company since 2013.
His resignation comes amid claims by the contractor Future Generation Joint Venture that the project has blown out by $2.2 billion.
In a statement to the ABC earlier this week, Mr Broad said the Snowy 2.0 project had been impacted by the COVID-19 pandemic and supply chain issues, but he rejected the contractor's cost blowout claims.
"Snowy Hydro rejects the reported $2.2 billion claim," Mr Broad said in a statement.
"Snowy Hydro has paid all amounts that Future Generation Joint Venture is contractually entitled to."
Mr Broad said all claims submitted by the contractor were assessed "appropriately," in accordance with the contractual requirements.
Climate Change and Energy Shadow Minister Ted O'Brien said in a statement he was concerned about reports that Mr Broad had been sacked from the role.
"Reports that Chris Bowen has directed Snowy Hydro's executive board to sack Snowy Hydro chief executive Paul Broad today for providing advice that he disagrees with is deeply concerning," Mr O'Brien said.
"[Mr] Bowen is on an energy rampage as he seeks to shut down the voices of industry experts that have a different point of view."
Climate Change Minister Chris Bowen did not respond to direct questions from the ABC about Mr O'Brien's claims.
In a statement, a spokesperson said the government valued Snowy Hydro and the "critical role" it played in supporting a changing grid.
"The Albanese Government notes the resignation today of Snowy Hydro CEO Paul Broad after almost ten years of service," a spokesperson said.
"[It] thanks him for his work in the energy market over that period."
The $5.1 billion Snowy Hydro 2.0, first announced by then-prime minister Malcolm Turnbull in 2017, is 19 months behind schedule.
It has pushed expected electricity production beyond the planned start of 2025.
In a statement, Snowy Hydro said the board would start recruitment to fill Mr Broad's position.
"The Snowy Board will now commence a process to identify new leadership," the statement said.
It said chief operating officer Roger Whitby would lead the organisation on an interim basis, with support from Mr Broad to facilitate a smooth transition.