TORONTO — The future of Bombardier's sole Canadian CSeries order is in question after Ottawa confirmed it would not allow passenger jets to fly out of Billy Bishop Toronto City Airport. Transport Minister Marc Garneau tweeted Thursday night that the government will not reopen an agreement with the City of Toronto and Ports Toronto that would need to be renegotiated to extend the runway at the island airport and permit jets. In 2013, Porter Airlines placed an order for a dozen of the 110- to 125-seat CSeries aircraft on the condition that they would be allowed to fly at the airport. Porter Airlines declined comment. If Porter walks away from the order it would deal a blow to Montreal-based Bombardier, which has been scrambling to sell its CSeries jets. The Quebec government has agreed to give Bombardier US$1 billion to help complete development of the CSeries in exchange for a 49.5 per cent stake in the project, which has experienced delays and cost overruns. The provincial government has also made it clear that it would like to see Ottawa step up with funding, though Prime Minister Justin Trudeau said earlier this week that Bombardier would need to make a "strong business case" for such a request.