By Marc Frank

HAVANA (Reuters) - Havana on Sunday blamed Washington for a surge of Cubans trying to reach the United States by land and sea, accusing the Obama administration of encouraging illegal and unsafe immigration.

Tens of thousands of Cubans over the last two years have flocked to the U.S.-Mexican border and taken to the sea in hopes of reaching Florida, fearing a growing detente between the Cold War foes will lead to a change in U.S. policy.

Under a 1960s law, the Cuban Adjustment Act, the Communist-run country’s citizens are treated as legal immigrants if they set foot on U.S. soil, while migrants from any other land are considered illegal.

A government statement carried by local media and announcing the arrival of 14 Cubans deported by Colombia, said they were the “victims of the politicization of the migration issue by the U.S. government which stimulates illegal and unsafe immigration.”

The government said its citizens “receive differential treatment ... they are immediately and automatically admitted ... including if they arrived by illegal means.”

The statement said the policy contradicted normalization efforts.

Colombia last week announced that more than 1,000 Cubans stuck in the country, and who were trying to reach the United States, would be deported.

Colombia is just the latest government to crack down on Cubans who legally visit the region and then illegally, often with the help of human smugglers, pass through their territory on the way to the Mexican border.

A Pew Research Center report released on Sunday said that during the first 10 months of fiscal 2016 more than 46,500 Cubans had arrived and been admitted to the United States without visas, compared with more than 43,000 in 2015 and just over 24,000 in 2014.

As the long trek through the region becomes more difficult and costly, more Cubans may take to the sea.

“Both my children say they are going to leave by boat as soon as they can,” a distraught mother in westernmost Pinar del Rio province said, requesting anonymity.

“I keep telling them it is too dangerous. But they won’t listen, they are determined to go now,” she said.

The U.S. Coast Guard on Saturday reported that since Oct. 1, at least 5,786 Cubans have tried to migrate to the southeastern United States by sea and been intercepted, compared with 4,473 in federal fiscal year 2015.

(Reporting by Marc Frank; Editing by Stephen Powell)