Australian prime minister Anthony Albanese met with Sir Keir Starmer for the first time on the sidelines of the Commonwealth Heads of Government Meeting (Chogm) in Apia, Samoa.
The Climate and Energy Partnership was announced on Thursday, focusing on the "accelerated" development of renewable energy like offshore wind and green hydrogen through shared cooperation.
A joint statement referenced no specific initiatives, instead focusing on net-zero emissions targets set by both nations.
Sir Keir said Australia and the UK shared many things in common.
"This partnership underscores our commitment to powering up the UK with clean energy projects that will benefit communities across the country," he said.
"Together, we're delivering better futures for our two countries, whether that's through protecting our national security with projects like AUKUS or delivering on our net zero commitments."
Mr Albanese said: "This partnership will ensure we maximise the economic potential of the net zero transition, and build on our long-standing cooperation on international climate action and shared commitment to reach net zero emissions by 2050."
We share a vision for a modern and transformed Australia-United Kingdom relationship, which delivers tangible benefits and prosperity to both our nations and the Indo-Pacific."
Other discussions between the two leaders centred around the Australia-UK free trade agreement, security and stability across the Indo-Pacific and negotiations for a bilateral treaty announced in September to develop the SSN-Aukus submarine for both nations.
The biennial meeting is being hosted by Samoan prime minister Fiame Naomi Mataafa and is expected to focus heavily on regional security and tackling climate change.
King Charles addressed the gathering on Thursday.