EXCLUSIVE: Robert Oulds claims Lord Cameron may "surrender" the Rock's airport to Spain", a move he said would "cut Gibraltar's lifeline to the world".
Tory MPs have expressed 'considerable alarm' over the concessions the UK has agreed to, and questioned whether British sovereignty of the territory might be compromised as a result of the deal.
The allegation comes as MEPs vote to keep the British territory on the EU's money-laundering watchlist, despite European Commission's decision to remove it.
The UK and Spain hailed the "significant progress" in talks made this month over the post-Brexit deal set to define Gibraltar's future relationship with the EU.
As post-Brexit negotiations continue, the future of Gibraltar remains uncertain, with both Britain and Spain vying for control over the strategic territory.
A Red Arrows aerobatics display scheduled for last September was reportedly cancelled after a Spanish official warned it would be a 'hostile act' and that its response would likely 'not be mild'.