The United States has agreed to provide Poland with surface-to-air Patriot missile systems, as the eastern European country hosts US President Donald Trump ahead of a G20 summit of world leaders in Germany.

“A memorandum was signed tonight that the US government has agreed to sell Poland Patriot missiles in the most modern configuration,” said Poland’s Defense Minister Antoni Macierewicz during a press conference aired on the country’s public television on Thursday morning.

“I am glad that I can pass on this information on the day of President Trump’s visit to Warsaw," he added.

Back in May 2010, US Patriot missiles were deployed to Poland’s northwestern town of Morag as part of international drills but were later moved farther away from the Russian border, to the towns of Torun and Ustka, reportedly due to Moscow’s objections.

In March, Warsaw said that it expected to sign a deal worth up to $7.6 billion with Raytheon, a major US defense contractor and industrial corporation, to purchase eight Patriot missile systems by yearend.

The polish government views the deal as central to a comprehensive modernization of its armed forces by 2023. Two-thirds of Poland’s military equipment still dates to the Soviet era. Its armed forces have also suffered from decades of under-investment.

The deal can also be perceived in line with NATO’s military buildup in Eastern Europe against what it considers to be a “Russian threat.”

Russia, which views the deployment of NATO forces near its borders as a provocation, has strongly denied any plans to invade Poland or the Baltic countries. It has repeatedly slammed NATO’s military buildup near its borders, saying such a move poses a threat to both regional and international peace.

The news of the US-Poland Patriot agreement came a day after President Trump arrived in the Polish capital, Warsaw, where he is expected on Thursday to give a major speech.

According to the White House, Trump would in his speech lay out his vision for America’s relations with Europe and NATO member states, “and what that means for American security and American prosperity.”

Meanwhile, the 12th summit of the Group of Twenty (G20) will be held on Friday and Saturday in the German city of Hamburg, where Trump is likely to meet with his Russian counterpart Vladimir Putin for the first time.