HAVANA (AFP) - US and Cuban officials did not set dates to reopen their embassies during historic talks on Thursday but agreed to meet again on the issue, US and Cuban officials said.

"I can't tell you exactly when (reopening embassies) will happen," Roberta Jacobson, the US assistant secretary of state for the Western Hemisphere, told reporters.

Cuban delegation chief Josefina Vidal said more talks would take place "in the future" but no date or place have been set yet.

Jacobson, who became the highest-ranking US official to visit Cuba in 35 years, said the meeting in Havana's Convention Centre had been "positive and productive" but that normalising relations that were cut that in 1961 would take time.

"Those issues that are part of the full range of normalisation are complex and they reflect profound differences between our two countries and will continue to be discussed," she said.

"We have... to overcome more than 50 years of a relationship that was not based on confidence or trust," she said.

"So there are things that we have to discuss before we can establish that relationship."