Downing Street welcomed the Bombardier deal, saying it would protect high-skilled jobs at the plant in Northern Ireland

Canadian manufacturing group Bombardier announced Thursday it was selling its aerostructures business to US firm Spirit AeroSystems, involving operations in Belfast, Casablanca and Dallas, in a $1.2 billion cash-plus-debt deal.

Bombardier announced its willingness to sell these assets last May as part of a broad restructuring to focus on trains and business aircraft.

In a statement, Bombardier said the US firm would take over operations in Belfast, which assembles the wings for the Airbus A220.

Spirit AeroSystems will also acquire Bombardier's operations in Casablanca and a plant in Dallas specialising in maintenance and repairs.

The price includes $500 million (450 million euros) in cash and around $700 million in debt.

The 2019 revenues for the three operations are expected to be approximately $1 billion.

A spokesman for Prime Minister Boris Johnson's Downing Street office welcomed the deal.

"This is great news for Northern Ireland and the highly skilled and dedicated workforce," he told reporters.

"The Belfast plant is one of the most important aerospace facilities in the UK and this investment from Spirit AeroSystems is a significant boost for jobs and businesses in Northern Ireland.

The British trade union Unite welcomed the deal for the Belfast facility, which employs more than 3,500 people.

British trade union Unite said the deal "offers hope" for Bombardier workers in Northern Ireland

"We are pleased that Bombardier has heeded our call to be a responsible seller and the need for Bombardier aerostructures production to be transferred as a whole to a company with an excellent track record in aerospace rather than a short-termist hedge fund," said assistant general secretary Steve Turner.

"It is a sale that offers hope for a positive future for Bombardier workers in Northern Ireland and their colleagues in the supply chain."

Bombardier, which has been in a difficult financial situation for several months, has decided to consolidate all of its aeronautical activities into a single entity named Bombardier Aviation, with in Montreal, Mexico and Texas.

The sale saw Bombardier rise 11 percent in early Thursday trade on the Toronto Stock Exchange to 1.76 Canadian dollars at around 1342 GMT.