On 18 May, the decision to keep full independence as a point for negotiation was vindicated by the arrival in Europe of news that, over a month previously, Admiral Rodney had gained the victory over the French in the Caribbean, which he and Britain so desperately needed, capturing the French Admiral de Grasse. Grenville was sent back to France to negotiate with both the Americans and the French, but found himself making little progress with either—only when Oswald told him about the Canada proposal did he begin to understand why, and he wrote an indignant letter to Charles Fox, who was no happier about what his hated rival Shelburne was doing. Having exposed the trickery to his colleagues, at the end of June Fox proposed a vote that the independence of the United States should be accepted without preconditions, but in the light of Rodney's victory and the consequent French weakness, this was rejected (though the news that a combined Spanish and American fleet had forced the surrender to Spain of the Bahamas arrived in Britain at about this time).