Right-back Bellerin has come to London because he has been promised a fast track to the first team.
Bellerin, speaking to Spanish TV programme Punto Pelota, said: "I was at home and my father called me to say Arsenal had been on the phone.
"We decided to go there to see how things are. I hadn't made up my mind because I'd been at Barcelona all my life so it was very difficult.
"We met Mr Wenger and it went so well. It was all too much for me but I paid full attention to everything he said. When there is a team that guarantees you can play in the first team and above all in the Premier League, then it is very difficult to say no.
"Mr Wenger was explaining to me how the club was and the project they had prepared for me and above all he wanted to get to know me."