Authorities said Saturday that more discussions are needed before a Spanish research team can examine a tomb purportedly holding Christopher Columbus' remains, setting back efforts to determine if claims that he is buried in Spain are true.

  The government initially had agreed to reopen the tomb on Feb. 15, but authorities later backtracked after the event was heavily publicized.

Dominican authorities were upset with reports that researchers would do more than visually inspect the bones. The dispute over which set of remains are authentic has simmered for more than 100 years.

The tomb is housed in a sprawling monument to Columbus in the Dominican capital of Santo Domingo. Spanish investigators had planned to look at the bones to see if they were stable enough to take DNA samples.

If the genetic material was intact and the Dominican government approved, the Spanish team had planned to check the DNA against samples from Columbus' relatives buried in Seville, along with remains in a cathedral in Seville that Spain says are those of Columbus himself.

But Andy Mieses, in charge of the monument, said the government wants further discussions to ensure there are no misunderstandings about the purpose of the opening. A new date for the opening was not set.

The Spanish team has examined DNA from the bones in Seville along with DNA from remains widely believed to be those of Columbus' brother Diego and from bones known to belong to Columbus' son Hernando. The latter two sets are also in Seville.

Cross-checking the three samples has proved inconclusive because of the deteriorated state of the DNA, prompting the researchers to want to examine the bones in Santo Domingo.

Columbus was buried in the northern Spanish city of Valladolid, where he died on May 20, 1506. He had asked to be buried in the Americas, but no church of sufficient stature existed there. Three years later, his remains were moved to a monastery on La Cartuja, next to Seville.

In 1537, Maria de Rojas y Toledo, widow of another of Columbus' sons, Diego, sent the bones of her husband and his father to the cathedral in Santo Domingo for burial. They remained there until 1795, when Spain ceded the island of Hispaniola to France and decided Columbus' remains should not fall into the hands of foreigners.

A set of remains that the Spaniards believed were Columbus' were first shipped to Havana, then back to Seville when the Spanish-American War broke out in 1898.

In 1877, however, workers digging in the Santo Domingo cathedral unearthed a leaden box containing bones and bearing the inscription, "Illustrious and distinguished male, Christopher Columbus."

The Dominicans say these are the genuine remains and the Spaniards took the wrong body with them back in 1795.