March 3 (Reuters) - Nustar Energy said on Monday it signed long-term agreements to lease crude oil storage at its two Atlantic storage terminals. The San Antonio, Texas-based company said it entered into an agreement with an unnamed national oil company for 5 million barrels of light crude oil storage capacity at its St. Eustatius terminal in the Caribbean, with the first oil shipment expected this week. The second deal was with a major U.S. oil company that leased 3 million barrels of light crude oil storage at Nustar's Point Tupper terminal in Nova Scotia, Canada, that will go into effect this summer. The St. Eustatius terminal has a tank capacity of up to 13.4 million barrels while the terminal in Point Tupper, located about 700 miles from the New York harbor, can store up to 7.7 million barrels. Nustar did not immediately respond to requests for comment. The company did not disclose the identity of the parties to the agreement and the value of the contracts.