The British Olympic Association (BOA) is "dismayed" by the decision of a group of athletes to continue pursuing legal action while holding talks over the International Olympic Committee's Rule 40.
Sprinter Adam Gemili has described the controversial statute which places restrictions on the commercial activities of athletes during a defined Games period as "ridiculous, unjust and unfair".
Twenty names are listed as claimants on a legal letter sent to the BOA last month, but the governing body will defend itself robustly in frustration at the methods being used by the British athletes.
"The BOA can confirm it has formally responded to the recent legal challenge brought against the BOA's interpretation of the IOC's Rule 40 in the UK," it said in a statement.
"Since we learned of the legal challenge - through the media - we have proactively sought to understand the athletes' concerns and who, in fact, we are negotiating with - athletes, agents or commercial organisations.
"Last week we had a positive meeting with representatives of the athletes who have challenged Rule 40.
"We are open to dialogue and reaching a positive outcome that balances the desire for individual athletes to maximise their personal sponsorship revenues with the need to preserve and enhance a system that has collectively sold rights for the benefit of the whole of Team GB, including smaller sports and less high-profile athletes.
"However, despite those encouraging conversations, we have been dismayed by the ongoing legal tactics being conducted in the background, which in no way reflects the spirit of the discussions held.
"Therefore we have been forced to respond fully and robustly to the legal challenge and have done so in the best interests of all of the athletes we serve and the BOA - a not-for-profit independent organisation that receives no tax payer or Government funds."