Companies involved in the '100 billion barrels of oil' field under Gatwick Airport may not be able to explore anymore

The Horse Hill oil field, which was at one point tipped to garner "100 billion barrels of oil" for Britain by the oil exploration group UK Oil & Gas Investments, is now in the spotlight again after another oil company which has a stake in the region said its exploration licences are about to run out.

Doriemus, which is a group that acquires companies and projects within the oil and gas sector in Europe, said in a long regulatory statement, that one exploration licence (PEDL137) expires on September 30, 2015.

Its second licence (PEDL246) expires on June 30, 2015.

Doriemus added that the operator of the two licences, Horse Hill Developments Limited (HHDL), has already applied to the Oil & Gas Authority for a one year extension of the exploration period of PEDL137.

This announcement is a big deal for oil developers in the field. If licences do not get extended, it means companies cannot continue to explore and determine the amount of oil underneath the ground and how much is likely to be extracted.

The PEDL137 and PEDL246 licenses are held 35% by Magellan Petroleum Corporation and 65% by Horse Hill Developments Limited, which is a special purpose company that holds the rights to a 65% participating interest and operatorship in the onshore Horse Hill Oil Field in the Weald Basin, West Sussex.

Doriemus has a 10% interest in Horse Hill Development.

This is the latest issue to hit developments in the oil field which was touted to be the one of the biggest onshore oil discoveries in Britain.

Earlier this month, UKOG said in a regulatory statement that up to it made a "significant discovery" onshore beneath the South of England, after it drilled a well at Horse Hill near Gatwick Airport, West Sussex, last year. The number comes from the fact that UKOG said that the local area could hold 158 million barrels of oil per square mile and from management estimates confirmed on the BBC.

Stephen Sanderson, CEO of UKOG, told the BBC after the announcement that the group potentially uncovered up to 100 billion barrels of oil near Gatwick Airport.

"Based on what we've found here, we're looking at between 50 and 100 billion barrels of oil in place in the ground. We believe we can recover between 5% and 15% of the oil in the ground, which by 2030 could mean that we produce 10%-to-30% of the UK's oil demand from within the Weald area," Sanderson said.

However, the company has since said it doesn't actually know how much oil is underneath the ground.