ANKARA, Turkey (AP) — Turkish President Recep Tayyip Erdogan has promised to stand in solidarity with the United States in its struggle against the coronavirus pandemic and as it recovers from the outbreak.

In a letter sent to President Donald Trump, Erdogan also said he was following “with appreciation” the American leader's efforts to control the outbreak.

The letter was sent Tuesday along with a planeload of personal protective equipment that Turkey donated to the U.S. It was made public on Wednesday.

Erdogan wrote: “I am very pleased to observe that, thanks to your measures, America has taken the first steps towards normalization by achieving a downward trend in the number of new cases.”

“You can be sure, as a reliable and strong partner of the U.S., we will continue to demonstrate solidarity in every way possible,” Erdogan wrote.

Turkey sent 500,000 surgical masks, 4,000 overalls, 2,000 liters (528 gallons) of disinfectant, 1,500 goggles, 400 N-95 masks and 500 face shields. Turkey has sent similar medical equipment aid to a total of 55 countries — including Britain, Italy and Spain.

Erdogan and Trump have maintained a close personal relationship despite a series of differences between Ankara and Washington, including policy on Syria and Turkey's decision to purchase the S-400 Russian missile defense system that the U.S. says poses a threat to its F-35 stealth fighter jets and to NATO.

The U.S. removed Turkey from the fighter jet program and has threatened sanctions if the Russian system is deployed.

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