WASHNGTON – Russia's military presence in the Crimean Peninsula in Ukraine has been described as an "invasion" and a "takeover" of the region by troops that now have surrounded two marine bases in an ongoing stand-off.

However, Russian troop movements on the Crimean Peninsula are permitted under a 1997 Partition Treaty signed between Russia and Ukraine, as long as there are not more than 25,000 Russian troops.

At present, the Russians have about 16,000 troops on the peninsula, which means a further increase of troops would be permitted.

The Kremlin contends the move is to protect ethnic Russians who make up a majority of the population on the peninsula and in eastern Ukraine. Moscow asserts that ethnic Russians, especially in the Crimea, are being threatened by ultra-nationalists, as WND recently reported.

Meantime, there is concern on Capitol Hill that Russian troop movements were not anticipated by the U.S. intelligence community, resulting in impending oversight hearings to find out why.

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According to House Intelligence Committee Chairman Mike Rogers, there was debate within the intelligence community about whether Russian troops were on the move in Crimea, prompting public allegations that the Obama administration was caught by surprise.

The treaty

In addition to the limit of 25,000 troops, Russia Today said the agreement allows on Crimean territory 24 artillery systems with a caliber smaller than 100mm, 132 armored vehicles and 22 military aircraft.

Further, there are five Russian naval units stationed in the port city of Sevastopol as allowed under the treaty. The units are:

The 30th Surface Ship Division, which is formed by the 11th anti-submarine Ship Brigade. It comprises the Black Sea Fleet's flagship missile cruiser, Moskva, Kerchg, Ochakov, Smetlivy, Ladny and Pytivy, as well as the 197th Landing Ship Brigade, which consists of seven large amphibious vessels.

The 41st Missile Boat Brigade, which includes the 166th Fast Attack Craft Division consisting of Bora and Samum hovercrafts and the small missile ships Mirazh and Shtil and the 295th missile Boat Division.

The 247th Separate Submarine Division, consisting of two diesel submarines, the B-871 Alrosa and B-380 Svyatoy Kryaz Georgy.

The 68th Harbor Defense Ship Brigade, consisting of four vessels of the 400th Anti-submarine Ship Battalion and 418 Mine Hunting Ship Division.

The 422nd Separate Hydrographic Ship Division comprising the Cheleken, Stvor, Donuzlav andGS-402 survey vessels and hydrographic boats.

Two Russian air bases in Kacha and Gvardeysky.

Russia also has coastal forces that consist of the 1096th Separate Anti-Aircraft Missile Regiment in Sevastopol and the 810th Marine Brigade, which includes 2,000 marines.

Sources point out that the Russian military units are restricted to their bases, although there are persistent reports that Russian troops are swarming all over the peninsula.

The sources say that Russian President Vladimir Putin moved troops into Crimea in response to a request from authorities of the Ukrainian Autonomous Republic of Crimea.

The prime minister of the Crimean autonomous region is Sergiy Aksyonov, a pro-Russian politician who was elected by Crimea's regional parliament.

Aksyonov has given orders to Ukrainian naval forces on the peninsula to disregard any orders from the "self-proclaimed" interim government in Kiev, which took over following the ouster of the democratically elected Ukrainian president, Viktor Yanukovych.

Yanukovych has sought refuge in Moscow.

On March 1, Rear Admiral Denys Berezovsky, who had been appointed chief of the Ukrainian navy only a day earlier, announced alongside Aksynov that he had defected to the Crimean autonomous region.

The Russians have long-standing ties to the Crimean Peninsula. The links go back to Catherine the Great in the 18th century when Russia took Ukraine and Crimea from the Ottoman Empire.

In 1954, then-Soviet Premier Nikita Khrushchev, who was half-Ukrainian, gave the Crimea to Ukraine as a gift.

After Ukraine became independent in 1991 when the Soviet Union broke up, Russian President Boris Yeltsin entered into an agreement with Ukraine to base Russia's Black Sea fleet at Sevastopol under a lease until 2017. That lease recently was extended to 2042, although the Kiev interim government is attempting to abrogate that agreement.

Yeltsen also signed in 1994 the Budapest Memorandum, which was to guarantee the territorial integrity of Ukraine. As WND reported, however, it lacked any enforcement provision for military assistance should there be an attack.

The memorandum was signed in exchange for Ukraine giving up its nuclear weapons.

In addition to Yeltsin, U.S. President Bill Clinton, British Prime Minister John Major and Ukrainian President Leonid Kuchma signed the agreement.