In a letter sent to US President Barack Obama, Polish Prime Minister Donald Tusk congratulated the newly appointed leader.

“I am certain that your tenure in office will be a good time for the United States, as well as for Poland and the whole world,” the PM wrote.

The Polish PM went on to say that the two countries have significantly strengthened their partnership over the last year, and Tusk expressed his hope that the countries' targets will be met.

“I'm also counting on the fact,” the letter read, “that transatlantic cooperation will strengthen and be invigorated, because the world and Europe alike need the US's strong and open cooperation with those who desire peace and safety.”