Saudi Arabia's crown prince said on Saturday that the world's top oil exporter aims to reach "net zero" emissions of greenhouse gases, mostly produced by burning fossil fuels, by 2060 - 10 years later than the United States.
He also said it would double the emissions cuts it plans to achieve by 2030.
Crown Prince Mohammed bin Salman and his energy minister said Saudi Arabia would tackle climate change, but also stressed the continued importance of hydrocarbons and said it would continue to ensure oil market stability.
They were speaking at the Saudi Green Initiative (SGI) ahead of COP26, the United Nations climate conference in Glasgow at the end of the month, which hopes to agree deeper global emissions cuts to tackle global warming.
The United States, the world's second-biggest emitter, is committed to achieving net zero, meaning that it emits no more greenhouse gases than it can capture or absorb, by 2050. But China and India, the world's biggest and third-biggest emitters, have not committed to this timeline.
Amin Nasser, chief executive of the state oil giant Saudi Aramco, said it was counterproductive to "demonise" hydrocarbons. He said Aramco aimed to expand its oil and gas production capacity while also achieving net zero emissions from its own operations by 2050.
He called for more global investment to ensure adequate crude oil supplies.
Prince Mohammed said in recorded remarks that the kingdom aimed to reach net zero by 2060 under its circular carbon economy programme, "while maintaining its leading role in strengthening security and stability of global oil markets".
He said Saudi Arabia would join a global initiative on slashing emissions of methane by 30% from 2020 levels by 2030, which both the United States and the EU have been pressing.
U.N. Secretary General Antonio Guterres, in a phone call with Saudi King Salman bin Abdulaziz, welcomed the kingdom's initiatives to reduce emissions, state media said.
U.S. climate envoy John Kerry is due to attend a wider Middle East green summit in Riyadh on Monday.
The SGI aims to eliminate 278 million tonnes of carbon dioxide emissions per year by 2030, up from a previous target of 130 million tonnes. The crown prince said the SGI initiative would involve investments of over 700 billion riyals ($190 billion) in that time period.
Saudi Arabia's economy remains heavily reliant on oil, although the crown prince is trying to promote diversification.
Energy minister Prince Abdulaziz bin Salman said the world needed fossil fuels as well as renewables.
"It has to be a comprehensive solution," he said. "We need to be inclusive, and inclusivity requires being open to accept others' efforts as long as they are going to reduce emissions."
He said the kingdom's younger generation "will not wait for us to change their future".
He said net zero might be achieved before 2060 but the kingdom needed time to do things "properly".
Another Gulf oil producer, the United Arab Emirates, this month announced a plan for net zero emissions by 2050.
The non-profit Climate Action Tracker consortium gives Saudi Arabia its lowest possible ranking, "Critically insufficient".
Saudi Arabia's first renewable energy plant opened in April and its first wind farm began generating in August.
It does, however, have plans to build a $5 billion plant to produce hydrogen, a clean fuel, and state-linked entities are pivoting to green fundraising.
