By Lidia Kelly MOSCOW (Reuters) – Russia has reached a provisional agreement with Cuba to reopen a big Soviet-era base on the Caribbean island from which it once spied in the United States, a Russian security source said on Wednesday. “A framework agreement has been agreed,” the source told Reuters, confirming a report in the daily Kommersant newspaper that the reopening was approved in principle during a visit to Cuba last week by President Vladimir Putin. In Washington, State Department spokeswoman Jen Psaki declined to comment, noting there was no formal announcement from Moscow. Other U.S. officials were skeptical, questioning whether Russia would go through with what would be an expensive initiative with possible limited returns.