NATO members and Ukraine have condemned Moscow for what they called Russia's "deliberate destabilization of eastern Ukraine" and its military buildup in Crimea, the Black Sea peninsula it annexed from Ukraine in March.
"We condemn Russia's military build-up in Crimea," NATO Secretary-General Jens Stoltenberg said after a meeting in Brussels of the foreign ministers of 28 NATO nations and Ukraine on December 2.
"And we also condemn Russia's actions, which are undermining the security of Ukraine and have serious implications for the stability and the security of the entire Euro-Atlantic area," he added.
Stoltenberg also announced that NATO has launched four "trust funds" to help Ukraine reform its military -- which is fighting Russian-backed separatists who have seized large parts of the eastern provinces of Donetsk and Luhansk -- and improve security.
"We remain committed to assisting Ukraine to speed up the reforms and we are enhancing our support so Ukraine can better provide its own security. At the Wales summit we agreed to set up four trust funds for Ukraine. Today, these four trust funds are up and running," Stoltenberg said, referring to an alliance summit in September.
The funds will deal with four areas: logistics, command and control, cyber security and the retraining of military personnel. A fifth fund has been established recently to assist wounded soldiers.
In a statement, the foreign ministers strongly denounced Russia's "continued and deliberate destabilization of eastern Ukraine in breach of international law, including the provision of tanks, advanced air defense systems and other heavy weapons to the separatists."
Russia denies involvement in the conflict that has killed more than 4,300 people in eastern Ukraine since April, despite what Kyiv and NATO say is clear evidence of direct military support for the separatists.
Meanwhile, the Organization for Security and Cooperation in Europe (OSCE) said that Ukraine's military and separatist forces agreed "in principle" on a new cease-fire in the Luhansk region from December 5.
The OSCE said in a statement that the sides also agreed to withdraw heavy weapons from "the entire line of contact" in the region beginning on December 6.
A broader cease-fire deal signed in Minsk on September 5 has been regularly violated, and more than 1,000 people have been killed since.
On December 1, Ukraine's military said that it agreed with Russian representatives to a temporary cease-fire at the airport in Donetsk, the site of heavy fighting.
The Ukrainian military said shelling continued there on December 2, but the AFP news agency quoted a separatist leader in Donetsk, Andrei Purgin, as saying later on December 2 that Ukraine and the separatists "reached an agreement to halt fire at 6 pm Moscow time around Donetsk airport."
Russian military envoys and their Ukrainian counterparts have held meetings periodically since late August in an effort to agree on conditions that could ease fighting and demarcate territory between the government forces and the rebels.
With reporting by Reuters and AP