Last December US President Barack Obama and his Cuban counterpart Raul Castro had agreed to restore long-broken ties between their two countries.
According to reports from Havana, the Cuban foreign ministry said it "confirms the decision to restore diplomatic relations between the two countries and open permanent diplomatic missions in their respective capitals, from July 20."
Reopening of the embassies would mark the end of a more than 50 years of animosity.
Obama and Secretary of State John Kerry are scheduled to make an announcement regarding this at the White House later in the day.
Both countries are currently represented by interests sections, and US and Cuban diplomats are not allowed to go out of Havana and Washington without official authorisation from the host countries.
In a major breakthrough in late May, the US had removed Cuba from a blacklist of state sponsors of terrorism.