WARSAW (Reuters) - Poland hopes to buy the American Patriot air and missile defense system, Defence Minister Antoni Macierewicz said on Saturday, signaling a $5 billion deal may be struck despite the new conservative government’s initial doubts.

In April 2015, Poland’s centrist government said it would buy Raytheon’s Patriot missiles, a deal which the then opposition conservative Law and Justice (PiS) party said it would review should it come to power.

Following PiS’ election victory in October, the new government questioned whether the “original cost and timeline assumptions, as well as those regarding the scope of (U.S.) cooperation with Polish industry,” could be met, adding it might scrap the deal.

Raytheon was ready to build the system in 65 months, but the actual delivery date would depend on inter-governmental negotiations, the company said at the time.

“The real, long range aim of our plans is a sustainable ownership of an efficient air defense. We hope this could be the Patriot system”, Macierewicz said at a joint press conference with U.S. ambassador Paul W. Jones transmitted by private broadcast TVN24.

“We hope for effective negotiations,” Macierewicz added.