Suleiman called on Defense Minister Elias Mur to attend a national dialogue session scheduled for Tuesday "given that he has to have a say in the design of a national-defense strategy."
Lebanon is debating its security options amid a tense border situation with Israel. Lawmakers are divided internally over whether Hezbollah should maintain its weapons.
A 2009 measure grants Hezbollah, now holding Cabinet ministries, the right to keep its weapons. Opponents of the measure argue that gives Israel justification to stay on alert.
Michael Williams, the U.N. special coordinator to Lebanon, said during a meeting with Lebanese Prime Minister Saad Hariri in Beirut that a national dialogue was a welcome step, the U.N. news center reports.
"While this is important and positive, it should not detract from the importance of working toward a permanent cease-fire as called for in Resolution 1701," said Williams.
That resolution ended a 2006 war between Hezbollah and Israel. Williams is expected to brief U.N. Secretary-General Ban Ki-moon on the implementation of Resolution 1701 at a March 12 meeting.