Venezuela on Tuesday shut the maritime border with nearby Dutch Caribbean islands ahead of an opposition effort to bring in humanitarian aid from foreign territories including neighboring Curacao despite the protests of President Nicolas Maduro.Maduro has rejected offers of foreign aid, denying there are widespread shortages and insisting that the country's economic problems are the result of sanctions by Washington. Opposition leader Juan Guaido, who has been recognized by dozens countries as the legitimate head of state, has said that food and medicine provided in part by the United States will enter Venezuela by land and sea on Saturday.The closure blocks movement of boats and aircraft between the western Venezuelan coastal state of Falcon and the islands of Aruba, Bonaire and Curacao, said Vice Admiral Vladimir Quintero, who heads a military unit in Falcon. He did not provide a reason.Venezuela's Information Ministry did not immediately respond to a request for comment.Curacao's government, which has agreed to receive aid for Venezuela without being involved in its delivery, said in a statement that the closure was meant "to prevent humanitarian aid from getting in.""Curacao will not force in the aid, but it will continue to function as a logistical center," it said.The United States has sent tons of aid to Colombia's border with Venezuela. Maduro has mocked the effort as a "cheap show" by the United States, insisting Washington should help his government by lifting crippling oil sector sanctions. ‘Our dead bodies’Defense Minister Vladimir Padrino in a televised broadcast on Tuesday said Venezuelan troops would remain stationed along the country's borders to prevent territorial violations.Padrino, flanked by a cadre of top-ranked military officials, said opposition leaders would have to pass over "our dead bodies" to impose a new government. Guaido, who invoked articles of the constitution to assume the interim presidency, denounces Maduro as illegitimate.U.S. President Donald Trump on Monday warned members of Venezuela's military who remain loyal to Maduro that they would "find no safe harbor, no easy exit and no way out."Padrino said officers and soldiers remained "obedient and subordinate" to Maduro."They will never accept orders from any foreign government ... They will remain deployed and alert along the borders, as our commander in chief has ordered, to avoid any violations of our territory's integrity," Padrino said. Maduro, who won a second term last year in an election that critics have denounced as a sham, retains the backing of Russia and China and control of Venezuelan state institutions.Leaders of several Latin American nations plan to travel to Colombia's border with Venezuela on Friday ahead of the delivery of aid, Chilean President Sebastian Pinera said on Tuesday, adding that he had accepted an invitation from Colombia's president, Ivan Duque.It was not immediately clear which leaders would attend.Most Latin American countries now recognize Guaido as president, though Bolivia, Cuba and Nicaragua still support Maduro.Billionaire businessman Richard Branson is backing a "Live Aid"-style concert on Friday in the Colombian border city of Cucuta with a fundraising target of $100 million to provide food and medicine for Venezuela. Maduro's government has announced two rival concerts just across the border.