Airlines have begun positioning themselves for possible travel to the island nation, following the Obama Administration's announcement that it would begin steps to ease restrictions against Cuba.

The new policies, which begin Friday, no longer prohibit air carriers from scheduling regular flights to Cuba.

On Thursday, United Airlines said that it intends to offer regular commercial flights between its Houston and Newark hubs to the Caribbean island, subject to government approval.

"We plan to serve Cuba, subject to government approvals, and look forward to doing so from our global gateways of Newark and Houston," the airline said in a statement.

In addition, American Airlines, JetBlue Airways, Southwest Airlines and Spirit Airlines also expressed interest Thursday in the new regulations.

“We are reviewing the changes to the Cuba travel policy and will continue to be guided by the laws and policies of the U.S. government and the governments of the countries we serve as they evolve,” American said in a statement.  

American Airlines dominates many of the routes to Latin America with its hub in Miami. It's run charters to Cuba for more than 15 years, according to spokeswoman Martha Pantin. It now operates 12 to 14 weekly flights from Miami to Havana, Holguin, Santa Clara and Cienfuegos and from Tampa to Havana and Holguin.

Southwest, which just began its international service with a focus on the Caribbean and Mexico, is taking a wait-and-see approach.

“We’re aware of today’s announcements but it’s too soon to determine if or how they will impact our service footprint,” Southwest said.

Delta Air Lines, which operated more than 240 charter flights between October 2011 and December 2012, said it has no immediate plans to fly to Cuba. Spokesman Anthony Black noted that "having served there through our charter operations, the groundwork has been laid for us to possibly serve the market if an opportunity becomes available."

But passengers who want to travel to Cuba on commercial U.S. airlines won’t be able to book flights as they would for any other destination just yet.

Before any routes are established, the U.S. Department of Transportation must sit down with the Cuban government to negotiate a civil aviation agreement spelling out the rules for air travel between the two countries. Until that happens, the new rules will be on hold, the department said in a notice Thursday.

Under the relaxed rules, travel agents and airlines can book tickets for U.S. citizens to Cuba without a special license from the Treasury Department's Office of Foreign Assets Control. General tourist travel is still prohibited, but Americans authorized to visit Cuba and who fall into 12 categories that include religious, educational, cultural, professional, journalistic or humanitarian activities, need no longer apply for special licenses. Those traveling to the island will also be allowed to use credit cards, a restriction that complicated trips to Cuba in the past.

Only Congress can end the five-decade embargo that would lift all travel restrictions to Cuba.

 The Associated Press contributed to this report.