The Crystal Palace striker made his debut in France's World Cup qualifying win against Azerbaijan last night.
"It's magnificent," he told RMC Sport. "I already knew Clairefontaine (the training base), but coming for the A's (senior team) is indescribable, it's a dream.
"The first selection, you always wait for it because often you are pre-selected, so you have the hope of being called.
"Afterwards, even if you are not called... I am a guy who always remains ambitious. So if it is not today, it is tomorrow, and if it is not tomorrow, it is the day after tomorrow.
"When I received this call-up, I was really happy."
Mateta also recalled: “I always believed (in playing for the France national team.
"At Palace, right at the start, when I wasn’t even playing, I spoke about the France team in the dressing room and I had teammates like Wilfried Zaha who were laughing!
“They said that I was mad to think about the France team when I wasn’t even playing at Crystal Palace, but I responded saying that it was my objective and that I simply had to play to show what I could do.
“My dream has always been to play for the France team. I knew that I would get my chance.”