"I really trust her," the prime minister told journalists on Wednesday.
He said earlier that members of the Cabinet cannot make unilateral statements and should refrain from expressing personal opinions, especially on energy matters.
Vėsaitė has stated last week that Lithuania does not need the nuclear reactor proposed by Japan's Hitachi because it is too big. She also commented that Lithuania could have implemented the EU's Third Energy Package, directed against Gazprom's monopoly, at a slower pace.
Commenting on the economy minister's statements, Lithuania's President Dalia Grybauskaitė said that ministers making conflicting statements build an image of Lithuania as an unreliable country.
Butkevičius later said it was the minister's personal opinion and that Vėsaitė was not acquainted with specialist assessments of the country's energy strategy.
According to the Lithuanian prime minister, his country's position on the Third Energy Package remains unchanged and the reform will be implemented as planned.
The implementation of the Third Energy Package, which provides for unbundling of gas transmission, distribution, and supply operations, has sparked disputes between Lithuania and Gazprom.
Lithuania plans to unbundle the assets of Lietuvos Dujos (Lithuanian Gas), in which Gazprom holds a 37.1 percent stake, by the end of 2014 to bring it into line with EU requirements. Following the reorganization, Lietuvos Dujos' gas transmission pipelines will be spun off into a new company.
The Government of Lithuania plans to decide whether to continue with the Visaginas nuclear power plant project in the coming months. Based on the original plan, the three Baltic states would build the plant with Japan's Hitachi.
