New NATO Secretary-General Jens Stoltenberg has said that the cease-fire in Ukraine "offers an opportunity" but says Russia still has the power to destabilize the country.
Stoltenberg, speaking on October 1 in Brussels at his first news conference as NATO leader, said Russia must comply with international law and demonstrate it is respecting its international obligations.
"We see violations of the cease-fire" in Ukraine," he said.
The new NATO chief said he saw no contradiction between aspiring for a constructive relationship with Russia and being in favor of a strong NATO.
He added that NATO was not seeking a confrontation with Russia, but "cannot and will not compromise on the principles on which our alliance and the security in Europe and North America rest."
Stoltenberg told journalists that NATO had not received any specific request for a meeting of the NATO-Russia Council, but said that, if there was one, NATO would be ready to consider it.
Stoltenberg also welcomed the air campaign launched by the United States and alliance members Britain and France against Islamic State militants in Syria and Iraq.
He said NATO was ready to help Iraq with "measures of defense capacity building" if the Iraqi government requested it.
He stressed that NATO would come to Turkey's aid if Turkey, which shares a border with Iraq and Syria, came under attack.
Stoltenberg reaffirmed that Article 5 of the North Atlantic Treaty remains NATO's cornerstone.
Article 5 requires all alliance members to come to the aid of any NATO member state that is subjected to an armed attack.
The alliance's new civilian leader also welcomed the signing of the Status of Forces Agreement between NATO and Afghanistan, which he called "a decisive step forward" by the Afghan national-unity government.
Stoltenberg, who previously served two terms as prime minister of Norway, is the 13th secretary-general in NATO's 65-year existence.
He is the first NATO chief from a member state that borders Russia, and is considered a deft diplomat.
Stoltenberg replaced Denmark's Anders Fogh Rasmussen, whose hard stance toward Russia since the beginning of the Ukraine crisis attracted criticism from some alliance members such as Germany.
Traditionally, a European has headed NATO's civilian headquarters in Brussels, while an American officer holds the post of the alliance's supreme military commander.
With additional reporting by Reuters, AP, Interfax, and dpa