The 27-year-old midfielder will be plying his trade in the Premier League throughout the 2020/21 campaign after Arsenal activated his £45 million release clause mere hours before the deadline.

That way, the north London club were able to bypass negotiations with Atletico, who had stood firm on the release clause all summer, by paying up at the La Liga headquarters.

Atletico confirm the news on Twitter
Atletico confirmed the news on Monday night by tweeting that Partey had unilaterally terminated his contract by way of the release clause being released, essentially announced the move in tandem.

The tweet read: "@Arsenal pay Thomas Partey’s buyout clause at LaLiga headquarters. The player has unilaterally terminated his contract with our club."

The news was followed by confirmation that Lucas Torreira will be moving in the opposite direction on a season-long loan, which come as scant consolation for the bypassed Spanish side.
Then, approximately 15 minutes later, Arsenal reiterated what had already been revealed in Madrid by way of declaring #NoThomasNoPartey with a fantastic announcement video on Twitter.

Source: https://www.givemesport.com/1605108-arsenal-transfer-news-thomas-partey-joins-mikel-artetas-men-after-atletico-madrid-exit?autoplay=on

Good job.....we are gooners

We are gunner Partey!
Partey after Partey!!

nice

Has signed not have signed

Ebuka78:
Has signed not have signed

Thanks

Nice, Arsenal (gunner) used to be my club but do to their lack of winning Trophy makes me to leave

Arteta Good job👊👊👊

If only Arteta will play a 3man midfield of Xhaka, Partey and Ozil.
Xhaka with his long pass, Partey with his discipline and energy, then Ozil with his creativity. Since we couldn't get both Aour and Partey at a time.

Our team still lack creativity as we speak.
God's business anyway. Future looks bright with Ozil and Edu.

Welcome to London partey

So happy

.

fun, Arsenal (rifleman) used to be my league but do to their poor of winning Trophy makes me to leave

Good job for arteta and Good signing for arsenal my club. Wish us best in the future.