HAVANA (Reuters) - The number of Cuban Americans visiting Cuba is up 20 percent so far this year and will likely keep rising as Washington eases travel restrictions, the Cuban tour operator for U.S. traffic said on Wednesday. Antonio Diaz Medina, vice president of Havanatur, said arrivals picked up after the U.S. Congress in March eased a Bush administration measure that restricted Cuban American visits to once every three years. "The flights from the United States carried about 85,000 last year and so far this year arrivals have been about 40,000," Diaz said in an interview. Diaz said an additional increase in visitors was expected during the summer after President Barack Obama signed an executive order last month lifting all restrictions on Cuban Americans visiting relatives.