Delta and Virgin have strengthened their US-UK network with a new London-Portland, Oregon service as well as boosting frequency on other routes.
Delta will fly four-times weekly to the west coast city from Heathrow, starting May 26 2017.
The airline will also add a second Detroit to Heathrow service from March 26 2017, replacing Virgin's daily flight. As well as adding a third Atlanta-Heathrow frequency, taking over the second daily service currently operated by Virgin Atlantic, beginning May 25, 2017. Virgin Atlantic will continue to operate one daily Atlanta to London Heathrow service.
From March 26 2017, Virgin will start flying between Seattle and Heathrow, replacing the daily service operated by Delta.
A daily non-stop service between New York-JFK and Manchester will commence May 25, 2017 replacing the service currently operated by Delta. Delta will resume service for the winter 2017.
Virgin Atlantic executive VP Erik Varwijk said: "We are delighted to further optimise our joint services between the U.K. and the U.S. Our most fuel efficient Boeing 787-9 aircraft will add additional capacity to the successful Seattle route, enabling more customers to enjoy the Virgin Atlantic experience on this brand new aircraft.
"In Manchester, deploying our Airbus A330-300 aircraft on this route will allow us to further meet the growing demand from the Manchester market, now offering a total of six direct flights to the U.S. after the recently announced new services to Boston and San Francisco.
He added: "The network changes highlight the strength and flexibility of our joint venture, allowing us to make smart decisions that ensure the right aircraft are on the right routes for our customers."