Podolski had no qualms about testing himself at another of Europe's giants, saying: "I'm so happy to be joining Arsenal Football Club and to play in the Premier League.
Podolski continued: "The move to Arsenal provides a great opportunity for me to gain experience in international competitions at a top European club.
"I have made this decision not against Cologne but for this great opportunity and the good of my own individual development.
"This was not an easy decision for me at all, as Cologne, our fans and the city are something special for me. I will always carry Cologne in my heart.
"We need to pool our strengths now and have to be fully focused on our survival in the Bundesliga."