Jenkinson played for Finland as a junior international, but is now fully committed to England.
He told arsenal.com: "It was one of the hardest decisions I've ever had to make. I've made so many good friends over the years and I had many successful years representing the Finnish youth teams. I grew as a man and a player playing for Finland. I found myself flying on my own to different countries all over the world as a 17-year-old to meet up with the national team, it was an eye-opener. I thoroughly enjoyed it, and have so many great memories.
"I will always have a strong connection with Finland, but ultimately I had to follow my heart. I was born and bred in England, its where I grew up and where I call home. I had to look myself in the mirror and ask myself, 'What do you really feel?'. The answer to that was English, and that was the main reason behind my decision."
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