The NATO Secretary General is going to attend the opening of the NATO-Ukraine joint exercises "Ukraine-2015", which will be held at the Yavoriv training ground in Lviv region, Ukrinform reports. The head of the Alliance is also to take part in the meeting of the National Security and Defense Council of Ukraine. In addition, the document on opening of the NATO office in Ukraine is expected to be signed. "This visit will be the milestone,” Acting Head of the Mission of Ukraine to NATO Yehor Bozhok says. “In Soviet times, we were ready to repel attacks of the West. The reality shows that the threat comes from the East."