Ibrahimovic broke the news by posting a picture on Twitter of him arm-wrestling a devil. Alongside the post he wrote: “I UNITED it @ManUtd.”
Minutes later, it was confirmed by United and the Swede will wear the No.10 shirt at Old Trafford vacated by Wayne Rooney.
Ibrahimovic, 35, made 46 appearances and scored 28 goals for the club last season before suffering a knee injury, which ended the campaign prematurely.
But he’s now nearing on a return to full fitness and Jose Mourinho has moved to ensure he stays at Old Trafford.
Ibrahimovic has won championships in four different leagues since beginning his professional career with Malmo in 1999.
Ibrahimovic said: “I am back to finish what I started. It was always mine and the club’s intention for me to stay.
“I cannot wait to get back out on that Old Trafford pitch, but I also know that I have to take my time to make sure that I am ready.
“I have been working hard and will continue to do so to make sure I am in the best possible condition for my return to the pitch.”
Boss Mourinho added: “We are delighted Zlatan is on the road to recovery and we are equally delighted to have his ambition and experience back with us.
“After his contribution last season he deserves our trust and we will be patient waiting for him to return. I have no doubt that he will be important in the second part of the season.”
Ibrahimovic travelled to America to undergo an operation and was expected to be sidelined until the start of 2018.
United bosses decided to release the veteran striker after rejecting the chance to trigger a 12-month extension in his £300,000-a-week deal.
But Ibrahimovic was allowed to return to Manchester to use the club’s Carrington training complex for his rehabilitation.
United this afternoon released a video confirming Ibrahimovic’s return.
In it, the 35-year-old is seen smiling to the camera – clearly pleased with his decision to re-sign for Mourinho’s side.
The former Sweden international then dramatically walks off with the No10 shirt on his back.
But, before going through a door, he punches a punch bag in a sign he is raring to go.