According to Reuters:
Castro holds the record for the longest speech ever delivered to the United Nations: 4 hours and 29 minutes, on Sept. 26, 1960, according to the U.N. website. One of his longest speeches on record lasted 7 hours and 30 minutes on Feb. 24, 1998, after the national assembly re-elected him to a five-year term as president.
(The first part of the claim needs to be amended with the fact that it's the longest UNGA speech. At the UNSC there was a considerably longer intervention by an Indian representative, probably intended to delay/filibuster a decision, while "facts on the ground" were being established in Kashmir.)
Anyhow, my question is about the 2nd part of that paragraph. Is the 7.5-hours reelection speech a record in that category, if we restrict ourselves to heads of state/government? (You can include fist-time acceptance/victory speeches, if you think that would yield a different answer.)