<P> At 7: 15 am EDT on October 25, USS Essex and USS Gearing attempted to intercept Bucharest but failed to do so . Fairly certain that the tanker did not contain any military material, the US allowed it through the blockade . Later that day, at 5: 43 pm, the commander of the blockade effort ordered the destroyer USS Joseph P. Kennedy Jr. to intercept and board the Lebanese freighter Marucla . That took place the next day, and Marucla was cleared through the blockade after its cargo was checked . </P> <P> At 5: 00 pm EDT on October 25, William Clements announced that the missiles in Cuba were still actively being worked on . That report was later verified by a CIA report that suggested there had been no slowdown at all . In response, Kennedy issued Security Action Memorandum 199, authorizing the loading of nuclear weapons onto aircraft under the command of SACEUR, which had the duty of carrying out first air strikes on the Soviet Union . During the day, the Soviets responded to the blockade by turning back 14 ships that were presumably carrying offensive weapons . </P> <P> The next morning, October 26, Kennedy informed the EXCOMM that he believed only an invasion would remove the missiles from Cuba . However, he was persuaded to give the matter time and continue with both military and diplomatic pressure . He agreed and ordered the low - level flights over the island to be increased from two per day to once every two hours . He also ordered a crash program to institute a new civil government in Cuba if an invasion went ahead . </P> <P> At this point, the crisis was ostensibly at a stalemate . The Soviets had shown no indication that they would back down and had made several comments to the contrary . The US had no reason to believe otherwise and was in the early stages of preparing for an invasion, along with a nuclear strike on the Soviet Union if it responded militarily, which was assumed . </P>

Joint chiefs of staff during cuban missile crisis