In a heartfelt Instagram message, the popular north London artist said sorry to the fans who had bought tickets for the much-anticipated gigs .
The massive tour has clearly taken its toll on the singer's vocal cords, which doctors say have been damaged.
The shows were due to take place at the stadium on Saturday (July 1) and Sunday (July 2).
In the Instagram message, the multi-award winning singer said: "The last two nights at Wembley have been the biggest and best shows of my life.
"However I have struggled vocally both nights.
"I had to push a lot harder than I normally do.
"I went to see my throat doctor today this evening because my voice didn't open up at all today and it turns out I have damaged my vocal cords."
The singer, who trained at The BRIT School in Croydon, goes on to say that she is heartbroken by the decision to cancel the shows but adds she has already "maxed out on steroids and aids" for her voice.
In her desperation to perform and not let down her fans, she said she even considered miming just to go through with the concerts and be amongst her loyal followers.
She said: "I'm sorry for the nights you would have had with your loved ones and the memories you would have made together.
"I'm sorry for the time and money you've spent organising your trips.
"To not complete this milestone in my career is something I'm struggling to get my head around."
It is not known at this stage whether the shows will be rescheduled but refunds will be available if the concerts do not go ahead.
Earlier this week the artist revealed she may never tour again , saying that she was a "real homebody".
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