The two telecoms firms will hold equal voting rights, with Verizon paying BT an equalisation payment of $645m. The JV - which BT said was designed "specifically for a cloud-first world in the age of AI" - will have around 3,000 customers in more than 180 countries, with combined annual revenues of around $4bn.
The move is the latest by BT under chief executive Allison Kirkby to refocus the 180-year-old business on its domestic offering, having already agreed to shed its Italian and Irish units.
Kirkby said the deal - which remains subject to regulatory clearance - would create "a stronger, scaled connectivity partner, one that has the reach, innovation and investment to succeed. Today’s announcement marks a major milestone for BT International, and an important step forward for BT as a whole as we deliver on our UK-focused strategy."
Verizon chief executive Dan Schulman said: "Our international customers require secure, flexible connectivity that works seamlessly across borders and cloud environments. When we thought about how to best support them, this joint venture was the clear answer."
BT trimmed its 2027 full-year outlook following the announcement. Stripping out the international business, it now expects adjusted group revenue to come in between £17.1bn and £17.6bn, while adjusted EBITDA is slated to grow by between £8.1bn and £8.2bn.
It had previously forecast revenues of £19bn to £19.5bn, and EBITDA growth of £8.2bn to £8.3bn.
That did not stop the shares sparking on the announcement, however, and by 0900 BST they were trading 2% higher at 198.9p.
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