Australian oil and gas producer Amplitude Energy said it had signed a binding agreement to supply gas from its East Coast Supply Project (ECSP) to AGL Energy, the country's largest power producer.

Here are some details:

Deal covers about 20 petajoules of gas in total over an initial four-year period, with supply targeted to begin in the second half of 2028.

Amplitude, which produces gas from the Otway and Gippsland basins and is developing new supply in the Otway region, has been seeking to firm up demand for the ECSP.

Gas sales price in the deal is linked to oil benchmarks, a structure more typical of liquefied natural gas (LNG) contracts than domestic pipeline gas, highlighting tightening supply conditions and shifting pricing dynamics on Australia's east coast.

"This gas sales agreement reflects the strong demand we are seeing for reliable, domestic gas supply in Southeast Australia, as well as both parties' confidence in the ECSP," said Jane Norman, CEO of Amplitude Energy.

AGL Chief Commercial Officer David Moretto said the deal supports the utility's strategy to secure long-term domestic gas supply and bring new production to the market.

Shares in Amplitude rose as much as 6.7% to A$1.835 in early trade, outperforming the broader benchmark .AXJO, which was down 0.5%. AGL shares were down 0.6% at A$9.44.