Russia continues working on setting up a joint air defence system with all of its ex-Soviet military allies, including Kazakhstan.
Estonia's premier raised doubts Friday about the decision of three Baltic states to calculate how much money they lost under some 50 years of Soviet occupation.
Egyptian President Abdel Fattah al-Sisi called for NATO powers to help rebuild Libya, beset by violence since an uprising backed by the Western military alliance toppled leader Moamer Kadhafi.
NATO voiced concern that Russia's air attacks in Syria creates the risk of "an incident getting out of control," as Moscow and the US-led international coalition pursue different military objectives in the country.
Montenegro's premier expressed optimism that the tiny Balkan country would join NATO by the year's end, after the chief of the military alliance visited Podgorica and commended its reforms.
NATO secretary general Jens Stoltenberg said he welcomed President Barack Obama's decision to keep US troops in Afghanistan longer than planned as part of a "crucial" effort to support Kabul.
NATO Secretary General Jens Stoltenberg said there had been a "troubling escalation" in Russian military activity in Syria, after Moscow dramatically expanded its air campaign.
NATO General Philip Breedlove expressed concern Monday about the strength of Russia's military build-up in northwestern Syria and the apparent creation of a defensive "bubble" in the Mediterranean.
Russia is still sending weapons to separatist rebels battling the Ukrainian government despite a fresh truce in the war-torn east of the country.
NATO opened a training centre in Georgia as the ex-Soviet country eyes closer partnership with the Western military alliance amid tensions with Russia.
NATO strongly backed Turkey's fight against Islamic State militants in Syria at emergency talks.
Russia aims to boost the strategic positions of its navy on the Black Sea and seek to maintain an Atlantic and Mediterranean presence.
NATO hailed the Iran nuclear deal as a "historic breakthrough" that would strengthen global security, but urged Tehran to comply with the terms of the accord.
NATO has vowed to hold "continuous" military exercises in eastern Europe to deter Russia but has yet to respond to a request by Baltic states for a permanent brigade.
NATO head Jens Stoltenberg warned there was still a risk of heavy fighting in Ukraine and urged Russia to halt its support for pro-Moscow rebels.
US Secretary of Defense Ashton Carter will visit his European counterparts this week to take stock of cooperation with NATO.
NATO flexed its muscles in Poland during the first full drill of its new spearhead force, a structure designed to boost security on its eastern flank.
NATO head Jens Stoltenberg said Wednesday the alliance was implementing its biggest defence reinforcement since the Cold War.
Russian President Vladimir Putin said that Russia would have to defend itself if threatened, adding that NATO is "coming to its borders".
A majority of citizens from eight NATO countries are against sending arms to Ukraine to help battle pro-Russian separatists.