"We must not forget that NATO is an organization that has been created during the time of confrontation and for confrontation, that's why it cannot change its nature," Peskov told reporters in Moscow.
"That is why any advancement by such an organization toward our borders will force us to take adequate counter-measures to safeguard own own security, our national security," Peskov stressed.
The Ukraine leadership, which came to power in 2014, is seeking membership of both NATO and the European Union for the country.
On September 2, the Ukrainian National Security and Defense Council endorsed a new military doctrine that called for the country to strive for NATO membership.
Earlier on Tuesday, Ukraine and NATO signed a joint declaration to intensify military technical cooperation.