Lord Moynihan, the British Olympic Association chairman, said he was "cautiously optimistic" the organisation would win their appeal against the World Anti-Doping Agency.
Lord Moynihan, Chairman of the British Olympic Association, has just left the court of arbitration for sport hearing. He said: "It's been a good day, a long day, the voice of the athletes has been heard today loud and clear."
"We expect the decision in about the month, we asked for quick decision."
Sprinter Dwain Chambers, who was banned from athletics for two years for taking illegal substances, told ITV News last week he wishes he "could turn back the clock."
Lord Moynihan, chairman of the British Olympic Association (BOA), said "it was a very important day" as the BOA appeals against the World Anti-Doping Agency's decision to allow British athletes, who have been banned for taking illegal substances, to compete at this summer's Games.
Lord Moynihan has just arrived at the court of arbitration for sport hearing in central London saying he was 'very confident' about the British Olympic Association's (BOA) case which will be heard by a panel of 3 sports lawyers.
The hearing will only last a few hours but the decision will not be due for another few weeks.
Dwain Chambers, one of those athletes affected by the current BOA by-law, is due to arrive back from Istanbul at 18.30 GMT later today with the bronze medal he won at the World Indoor Championships.
The British Olympic Association (BOA) will appear in front of the court of arbitration for sport (CAS) in an attempt to uphold its lifetime doping ban.
If CAS fails to uphold BOA's appeal against the World Anti-Doping Agency's decision, it will allow both sprinter Dwain Chambers and cyclist David Millar, who have both served bans for taking illegal substances, to compete in London 2012.
Chambers, who won a bronze medal in the 60m sprint at the World Indoor Championships in Istanbul at the weekend, said it would be "fantastic" if he could compete this summer.