"NATO does not seek confrontation. We don't want a new Cold War. The Cold War is history and it should remain history. We will continue to seek constructive and meaningful dialogue with Russia," Stoltenberg said.
However, the presence in Poland and the Baltic countries of four multinational battalions will be a clear signal that an attack on one ally will trigger a reaction from the whole alliance, Stoltenberg said.
'Desire to live in peace': President Duda
Polish President Andrzej Duda, the host of the NATO summit, said at a conference ahead of the official start of the gathering that the principal aim of the Western alliance is to defend peace.
"The events of recent years - the annexation of Crimea, the conflict in Donbas, the war in Syria, terrorism and mass migration - have particularly hit hard at our belief in the durability and stability of the existing international order," Duda said.
He added: "Among the citizens of our country there is increasing concern about the future of the world in the shape we have know it so far.
"Together we need to do everything possible to enable our citizens to achieve their basic desire, the desire to live in peace and free from uncertainty, fear and anxiety."
The summit is expected to confirm that NATO will deploy four international battalions on a rotating basis to Poland and the three Baltic countries, which fear potential Russian aggression following Moscow's annexation of Crimea in 2014.
'Reaching out for dialogue': Foreign Minister Waszczykowski
Polish Foreign Minister Witold Waszczykowski said just ahead of the summit that NATO members were reaching out for dialogue with Russia at the same time as strengthening the alliance’s eastern flank.
"Responding to threats in a military manner, we are not forgetting that we have diplomatic instruments, the instruments of dialogue," he said.
"While sending a signal to our great eastern partner, which is at the moment pursuing a fairly irresponsible military-political operation, while responding with military means by strengthening the [eastern] flank, we also want to respond reaching out for dialogue." (pk)