Our only issue is that we want to leave this place with honor, weapons and vehicles,'' one Ukrainian soldier said.
Blinken said Washington was considering all requests for military assistance from the government in Kiev, but that it would be unlikely to prevent an invasion of Ukraine, which is not part of NATO. Breedlove said the military alliance needed to think about its eastern members, particularly the former Soviet Baltic states of Lithuania, Latvia and Estonia.
"We need to think about our allies, the positioning of our forces in the alliance and the readiness of those forces...such that we can be there to defend against it if required, especially in the Baltics and other places,'' Breedlove said.
Breedlove said NATO was very concerned about the threat to Transdniestria, which declared independence from Moldova in 1990 but has not been recognized by any United Nations member state.
About 30 percent of its half million population is ethnic Russian and more than half of the total speak Russian as a mother tongue.
Russia has 440 peacekeepers in Transdniestria plus other soldiers guarding Soviet-era arms stocks. It launched a new military exercise, involving 8,500 artillery men, near Ukraine's eastern border 10 days ago.
"There is absolutely sufficient (Russian) force postured on the eastern border of Ukraine to run to Transdniestria if the decision was made to do that, and that is very worrisome,'' Breedlove said.
The speaker of Transdniestria's parliament has urged Russia to incorporate the region, which lies to the west of Ukraine.
The new leaders in Kiev have said Moscow could seek to link up pro-Russian regions in Moldova, and Georgia to Ukraine's east, in a destabilizing southern corridor with Crimea in the middle.
Russia's Deputy Defense Minister Anatoly Antonov was quoted by the state's Itar-Tass news agency as saying Russia was complying with international agreements limiting the number of troops near its border with Ukraine.
Moscow's ambassador to the European Union, Vladimir Chizhov, said Russia did not have "expansionist views''. Asked to give a commitment that Russian troops would not move into Ukrainian territory outside Crimea, he told Britain's BBC. "There is no intention of the Russian Federation to do anything like that.''
U.S. Senator John McCain, a Republican foreign policy specialist, told the same BBC show that Putin's actions in Ukraine were akin to those of Adolf Hitler in 1930s Germany.
"I think he (Putin) is calculating how much he can get away with, just as Adolf Hitler calculated how much he could get away with in the 1930s,'' McCain said.
Germany's Foreign Minister Frank-Walter Steinmeier underscored the huge potential repercussions of Russia's bid to redraw national borders in Europe.
"I'm very worried the unlawful attempt to alter recognized borders in our European neighborhood, 25 years after the end of the Cold War, will open Pandora's Box,'' he said.
Belarussian President Alexander Lukashenko, a close ally of Russia, accepted on Sunday that Crimea was now "de facto'' a part of Russia, but said the annexation set a "bad precedent.''
Western sanctions lost some of their sting on Sunday when Russia's SMP bank, whose main shareholders were targeted by U.S. sanctions, said Visa and MasterCard had resumed payment services for its clients.
The bank said it was glad the two biggest international payments systems had listened to its arguments to reverse Friday's suspension of services as it was wrong to target the bank, which was not itself subject to any sanctions.
Putin and Russian media had mocked the sanctions, which did not stop the Russian military completing its takeover of Ukraine's military bases in Crimea. Russia's defense ministry said on Sunday that its flag was now flying over 189 Ukrainian military installations on the peninsula.
The EU emphasized its support for the new pro-Western government in Kiev, signing a political agreement with interim Prime Minister Arseniy Yatseniuk last week.
It also promised financial aid for the government— which Moscow says came to power by a coup to overthrow Yanukovich after he rejected an EU trade deal in favor of closer ties with Russia—as soon as Kiev reaches a deal with the International Monetary Fund. The IMF will report on Tuesday.
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