TREVOR HUNNICUT U.S. President Joe Biden says he is developing comprehensive initiatives to make it difficult for Russian President Vladimir Putin to invade Ukraine and that he would not accept Moscow's "red lines," as fears mounted that the simmering conflict could erupt into war. A video teleconference between the two leaders is anticipated within days. More than 94,000 Russian troops are massed near Ukraine's borders, said Ukraine's defense minister, Oleksii Reznikov, who cited intelligence reports suggesting Moscow may be planning a large-scale military offensive for the end of January. Moscow, in turn, has accused Ukraine and the United States of…