(ANSA) - ROME, APR 10 - NATO is essential to ensuring global balance, President Sergio Mattarella said in talks with Czech parliamentary Speakers in Prague Friday. We must "recover the spirit of 2000 [when Eastern European countries joined NATO and the EU] of 'creative courage.' The transatlantic relationship must remain strong. NATO is essential to ensuring the balance of the global system. And it is useful to both sides," said Mattarella, in talks held in Prague with the presidents of the Chamber of Deputies (Lower House) and the Senate of the Czech Republic. (ANSA).