WASHINGTON, July 15 (Reuters) - U.S. President Joe Biden said on Thursday the United States is prepared to send vaccines to Cuba if it is assured an international organization would administer them but he is not considering easing U.S. policy around sending remittances to the country. Thousands of Cubans on Sunday staged the biggest anti-government protests in decades to demonstrate against an economic crisis that has seen shortages of basic goods and power outages. They were also protesting the government"s handling of the coronavirus pandemic and curbs on civil liberties. Dozens of activists were detained. "I"d be prepared to give significant amounts of vaccine, if in fact I was assured an international organization would administer those vaccines," Biden told reporters during a press conference after his meeting with German Chancellor Angela Merkel. With regard to remittances, or payments Americans can make to their families in Cuba, Biden said he is not going to do that now. Remittances to Cuba are believed to be around $2 billion to $3 billion annually and represent Cuba"s third biggest source of dollars after the services industry and tourism. "It is highly likely that the regime would confiscate those remittances or a big chunk of it," he said, while calling Cuba a "failed state" that is "repressing their citizens." Biden also said the White House is reviewing whether the United States can help Cubans regain internet access after Cuba"s government restricted access to social media and messaging platforms including Facebook (FB.O) and WhatsApp amid the protests. read more On a separate call on Thursday, a senior Biden administration official said the United States has contingency plans and a "robust presence" in the Florida Straits if it has to deal with any increased flow of migrants fleeing Cuba by sea. The official, speaking on condition of anonymity, reiterated U.S. Homeland Security Secretary Alejandro Mayorkas" admonition for Cuban migrants not to head for U.S. shores and said a senior Cuban official"s threat of "mass migration" reflects "a lack of care for the lives of Cubans who would risk their lives." A vintage car passes by in front of the U.S. Embassy in Havana, Cuba, January 12, 2017. REUTERS/Alexandre Meneghini A vintage car passes by in front of the U.S. Embassy in Havana, Cuba, January 12, 2017. REUTERS/Alexandre Meneghini The U.S. official said the protests "will obviously have an impact on how we proceed" with a review of Cuba policy that was launched soon after President Joe Biden took office in January. "We saw that when we came in that the Cuban regime was actually cracking down much more on the population and that was having a bearing on how we were actually analyzing some of the possible policy responses," the official told reporters on a conference call. The official said the administration was looking at revising policy with an eye toward helping the Cuban people, not the government of the Communist-ruled island. But the official stopped short of providing specifics or a timeframe for finishing the review, which had raised hopes of re-engagement with Havana after former President Donald Trump rolled back much of the Obama-era detente between the old Cold War enemies. Before the protests, Biden"s aides had been looking at a range of options, including easing the flow of remittances to Cuba and authorizing more family travel. Also under consideration has been whether to lift the designation of Cuba as a "state sponsor of terrorism," a label Trump gave to Havana days prior to leaving office. The official declined to say whether Cuba would be removed from the list but said Cuba"s designation placed a "statutory restriction" on some of the other policy options. Asked about the prospects for mass migration from Cuba, the official said: "We are actually urging people not to migrate." Cuban migrants are largely flocking to the U.S.-Mexico land border, not the U.S. coast. And in a sharp break from his predecessor, Biden has been letting most in pending the outcome of their asylum applications, according to government data.