From the New York Times: The Russian president, Dmitri A. Medvedev, assailed his Ukrainian counterpart on Tuesday, blaming him for anti-Russian policies that he said have brought relations between the two countries to “unprecedented lows.”

In a letter to President Viktor A. Yushchenko of Ukraine, Mr. Medvedev announced that Russia would not dispatch its new ambassador to Ukraine as planned, “given the anti-Russian course of the Ukrainian leadership . . .”

In his letter, Mr. Medvedev said relations between Russia and Ukraine had reached their lowest levels since the Soviet Union collapsed, lashing out among other things at Mr. Yushchenko’s pro-Western politics, especially his designs on NATO membership, which Russia views as a national security threat.

On a visit to Ukraine last month, Vice President Joseph R. Biden Jr. said the United States would continue to support Ukraine’s NATO bid, once again highlighting the issue, which is unpopular with many Ukrainians. (photo: Reuters)