President-elect Donald Trump on Saturday condemned a growing push to force recounts in three states pivotal to his Nov. 8 victory, confronting the Green Party-backed effort for the first time even as he worked to address key Cabinet vacancies.

The New York billionaire, who charged the election was "rigged" on a daily basis before his victory, called the developing recount effort "a scam" in a statement released by his transition team.

Trump had been ignoring Green Party nominee Jill Stein's fight to revisit vote totals in Wisconsin, Michigan and Pennsylvania. Wisconsin officials announced late Friday they are moving forward with the first presidential recount in state history.

"The people have spoken and the election is over," Trump declared Saturday. He added, "We must accept this result and then look to the future."

At the same time, Trump was scrambling to address unfilled administration jobs, having barely scratched the surface of creating the massive team needed to run the government before his Jan. 20 inauguration.

Experts say presidential transitions are periods of great vulnerability for the nation, and among the vacancies on the Trump team are leaders of the departments of State, Defense and Homeland Security.

Trump, who has virtually no experience in foreign affairs, offered a one-line tweet Saturday morning in reaction to the death of Cuban leader Fidel Castro -- "Fidel Castro is dead!" -- before issuing a more detailed statement.

"While Cuba remains a totalitarian island, it is my hope that today marks a move away from the horrors endured for too long, and toward a future in which the wonderful Cuban people finally live in the freedom they so richly deserve," Trump said.

His transition team did not respond to requests to clarify his Cuba policy, which was inconsistent during the campaign.

Trump first suggested he supported President Barack Obama's orders loosening the U.S. trade embargo on the island. He reversed himself less than a month before the election, however, vowing to overturn Obama's order unless Cuba meets demands including "religious and political freedom for the Cuban people and the freeing of political prisoners."

Meanwhile, the incoming president paid little if any attention Stein's recount push, but Democratic rival Hillary Clinton forced his hand on Saturday by formally joining the effort. Stein, who drew 1 percent of the vote nationally, is raising millions of dollars to fund the recounts.

"Because we had not uncovered any actionable evidence of hacking or outside attempts to alter the voting technology, we had not planned to exercise this option ourselves," Clinton campaign attorney Marc Elias wrote Saturday in blog post. "But now that a recount has been initiated in Wisconsin, we intend to participate in order to ensure the process proceeds in a manner that is fair to all sides."

Elias said Clinton would take the same approach in Pennsylvania and Michigan if Stein were to follow through with recount requests those states, even though that was highly unlikely to change the election outcome.

"Regardless of the potential to change the outcome in any of the states, we feel it is important, on principle, to ensure our campaign is legally represented in any court proceedings and represented on the ground in order to monitor the recount process itself," Elias wrote.

Clinton leads the national popular vote by close to 2 million votes, but Trump won 290 electoral votes to Clinton's 232, with Michigan still too close to call. It takes 270 to win the presidency.

Trump, who repeatedly challenged the integrity of the U.S. election system before his win, called the recount push "a scam by the Green Party for an election that has already been conceded."

"The results of this election should be respected instead of being challenged and abused, which is exactly what Jill Stein is doing," he said in the statement, which didn't mention Clinton's involvement.

Trump was spending the Thanksgiving holiday weekend with family at his Palm Beach estate, Mar-a-Lago. He had planned to focus on filling key administration posts over the working vacation. On Friday, he named Fox News analyst Kathleen Troia "KT" McFarland as deputy national security adviser and appointed campaign attorney Donald McGahn as White House counsel.

Trump planned to return to his New York home on Sunday ahead of a series of Monday meetings with prospective administration hires, including Sheriff David Clarke of Milwaukee County, Wisconsin. He's seen as a possible Homeland Security pick. Clarke's vocal opposition to the "Black Lives Matter" movement has made him popular with many conservatives.

Trump and Vice President-elect Mike Pence also have Monday meetings scheduled with Oklahoma Attorney General Scott Pruitt, Rep. Lou Barletta, R-Pa., former Security and Exchange Commission commissioner Paul Atkins, World Wide Technology chairman David Steward and General Growth Properties CEO Sandeep Mathrani.

Internal divisions over his choice for secretary of state have delayed that critical decision. The options include former New York Mayor Rudy Giuliani, who lacks foreign policy experience, but was intensely loyal to Trump, and 2012 Republican presidential nominee Mitt Romney, who aggressively opposed Trump's candidacy but is largely regarded as more qualified. Tennessee Sen. Bob Corker is also a possibility.