Poland’s defense minster said Friday that he expected to sign a multibillion-dollar deal with U.S. firm Raytheon to buy eight Patriot missile defense systems this year.

Antoni Macierewicz told reporters in Warsaw that the $7.6 billion deal was necessary in light of what he called “a growing threat from the East.” Poland has increased efforts to modernize its military since Russia annexed Crimea from Ukraine three years ago.

“Those systems allow us to guarantee the security of the Polish state,” Macierewicz said.

Deputy Defense Minister Bartosz Kownacki said the missile system would help protect against Russian missiles based in Kaliningrad, an enclave of Russian territory between Poland’s northeastern border and Lithuania.

Raytheon also expressed satisfaction that the deal was moving forward. Congress must approve any contract for the sale of advanced U.S. military technology.

Macierewicz said the Polish government and Raytheon “concluded a very important stage of our discussions on the acquisition of medium-range missile systems to ensure Poland’s security.” He said that some issues were still outstanding, but that the deal could be signed by the end of 2017 if all conditions were agreed upon.

The defense minister acknowledged the talks were sometimes difficult and said Raytheon’s earlier price estimate for the missile systems, $12.7 billion, was “unacceptable.”