Presidential spokeswoman Daiva Ulbinaitė said the invitations to heads of states and governments were signed by President Dalia Grybauskaitė and Prime Minister Andrius Kubilius. Diplomatic sources say the invitations were sent out back in 2011.
"Due to the large number of international and regional events that require participation of the same heads-of-state, mainly prime ministers, this semester is not suitable for a few NB8 countries for yet another meeting, the timing is particularly unsuitable for the current chairmanship of the EU, Denmark," Ulbinaitė told BNS.
The summit was scheduled for 23 April in the framework of Lithuania's duty to coordinate Nordic-Baltic cooperation this year.
In the presentation of its priorities last December, Lithuania's Foreign Ministry said that "the biggest planned event is the NB8 summit in Vilnius on 23 April. Presidents and prime ministers of Nordic and Baltic states have been invited to attend."
The meeting plans were first announced after a meeting of the region's prime ministers on 31 October. The initiative was then presented by the Lithuanian prime minister.
In an interview to BNS, Ulbinaitė said that "the last conversations on the NB8 summit took place at the meeting of Nordic and Baltic prime ministers in Stockholm in February. According to information available to the President's Office, the date and venue of the new meeting are yet to be finalized."
Baltic, Nordic and British prime ministers had the meeting in Sweden on 8-9 February.
According to press releases from the President's Office, Lithuania's president invited foreign leaders to the Vilnius meeting before and after the Stockholm summit. After a meeting with Baltic and Nordic prime ministers in Brussels, the President's Office said in a communiqué on 1 March that "the president invited heads of Nordic and Baltic countries to the Nordic-Baltic summit to be held in Vilnius in April."
According to an official communiqué, Grybauskaitė also invited Finland's president-elect Sauli Niinisto to the 23 April summit.
In Ulbinaitė's words, a possibility is considered to hold only one Nordic-Baltic summit this year and take advantage of other international and regional events for a better dialogue between Nordic and Baltic countries.
Prime ministers of countries around the Baltic Sea are scheduled to meet in Stralsund, Germany, on 30-31 May, and leaders of Baltic Sea states are due to meet in St. Petersburg in the fall to address Baltic Sea pollution and security matters.
The Lithuanian Foreign Ministry has said the idea of holding the summit could be addressed again in the fall.
"There was the idea of hosting the NB8 summit in Vilnius this year. A few dates were discussed with partners. A large number of events of a similar format and EU chairmanship of one of the Nordic neighbors, the idea will be addressed again in the fall, if there are issues that need to be discussed on the top level," the ministry said in a comment to BNS.
Started in 1992, the NB8 format covers intergovernmental Nordic-Baltic cooperation but is not formalized.
"Representatives of various institutions coordinate actions and meetings. A top-ranking Nordic politician has said there are no issues that we couldn't discuss on the telephone and continue the conversation over lunch the following day, if needed. This demonstrates a high level of informality and flexibility, which is the main feature of Nordic political and cultural identity," the Lithuanian Foreign Ministry said.