The Falkland Islands has already rejected the UK Government’s requests to ratify the Paris Agreement on climate change, where countries commit to cutting their fossil fuel emissions to keep global temperature rises below 1.5C.
The EU and more than 190 other states have signed with Iran, Libya and Yemen among the few countries which have refused to take part.
Asked how Mr Lammy viewed the Falklands development, a Foreign Office spokesman said it would offer no financial support for such a scheme.
“As the Foreign Secretary set out in his speech on the climate crisis last week, we are resetting the UK’s approach to climate and nature by rapidly delivering new more efficient ways to reduce emissions,” he said.
“Since 2001, the UK has ceased financial support for the fossil fuel energy sector, including in its overseas territories.
“The natural resources of all UK Overseas Territories belong to the individual territories. Exploration of natural resources on the Falkland Islands is a matter for the Falkland Islands government and the private companies concerned.”
A public consultation on the Sea Lion oil field held this summer is thought to have garnered widespread support from the islanders and a final decision now rests with the Falklands government.
It told The Telegraph it supported the scheme, despite the contradictions with UK policy.
Asked how it reconciled its plans with the Energy Secretary’s stance on new oil and gas projects, the Falkland Islands government stressed its independence from the UK, adding that no direct conversations had been held with Mr Miliband’s department since early July.
A spokesman said: “We completely appreciate the UK’s stance on climate change and understand their position on prohibiting any new hydrocarbon licensing within the UKCS [UK continental shelf], while existing licences are honoured.
“The matter of development of the natural resources of the Falkland Islands is a devolved matter and is for the people of the Falkland Islands to decide.
“Given the UK’s robust and continued support to uphold the Falkland Islanders right to determine their own future we would expect this to extend to our freedom to choose whether or not to develop a hydrocarbon industry, subject to all of the appropriate checks and balances.”
The Department for Energy Security & Net Zero declined to comment.
If developed, the Sea Lion field, which lies 150 miles north of the South Atlantic archipelago, is predicted to generate £4bn for the 3,700 Falklanders over the next 35 years, equivalent to around £1m per islander.