Ferguson has since made it clear he was unhappy with how the fallout was handled by the Scottish Football Association.
But after SFA chief executive Gordon Smith said on Wednesday that whoever takes over from sacked manager George Burley would be free to pick Ferguson and McGregor, the 31-year-old midfielder did not rule out a return.
"To be honest, the situation that arose yesterday from the comments made by the chief executive have taken me by surprise," Ferguson told The Herald.
"Firstly, I would like to clarify that I have never once said I would never play for my country again, as some people seem to have claimed.
"I made my feelings known in August about the way the whole situation was handled - and at the time admitted my deep regret for what had happened.
"I have no desire to go over old ground, I have moved on with my life. That was it as far as I was concerned.
"I have been thoroughly enjoying my football with Birmingham City and have been concentrating all my efforts on the next chapter of my career.
"So, clearly, there would be a lot for me to think about should the situation arise.
"I would have to speak to my family and those whom I have always trusted before any decisions could be made.
"That is, of course, if a call is made from the new manager. So I'll get on with things until I hear anything different."
Ferguson's drinking partner that night at Scotland's team hotel at the end of March, McGregor, was also banned from representing his country.
Reacting to Wednesday's news of his reprieve, the Gers goalkeeper told the Daily Record: "I have to say the news has come as a complete surprise.
"It was something I didn't expect but I'm delighted to hear that there is a chance for me to return to the international fold.
"Yes, I know I made an error but I do feel I have paid a very heavy price for it. Being told you will never play for your country again hit me like a sledgehammer at the time.
"Like every Scottish boy, I grew up dreaming of pulling on that shirt and playing in front of the Tartan Army. It broke my heart to think I would never get that chance again.
"This news means there might be a chance for me to return but I'm not arrogant enough to think I'd just walk straight back in. It will all depend on the next manager.
"If he should decide that I might be able to do a job for him, then I'd be ready and willing to answer the call. Until then, all I can do is try to continue to prove myself at Rangers."