Cuadrilla has produced first gas from its fracking site in Lancashire.
The energy company said it has started to see natural gas flow at the Preston New Road exploration well.
Despite the volumes being “small” at this stage, Cuadrilla said it was “significant” and showed the potential of the site.
CEO Francis Egan said: “Considering that we are only at the very start of fracturing operations and, given operating constrains, have not yet been able to inject as much sand into the shale as we had planned, this is a good early indication of the gas potential that we have long talked about.”
Mr Egan said the gas flow shows that fracking could make a “major difference” to UK energy supply.
He added:“This initial gas flow is by no means the end of the story.
“However it provides early encouragement that the Bowland Shale can provide a significant source of natural gas to heat Lancashire and UK homes and offices and reduce our ever growing reliance on expensive foreign imports.
“This week, three huge tankers carrying liquefied natural gas from across the world, including shale gas imported from the US, will dock in the UK to safeguard our winter gas supplies.
“If we are able to fully test these wells, without compromising on safety, we have the potential to make a major difference to UK energy supply, security and economic prosperity.”
The site has been subject to a number of recent stoppages due to “micro seismic” events.
Cuadrilla said these could not be felt at the surface and were only picked up due to its scanning technology.