In the latest fighting, the ministry reported intense overnight clashes between government troops backed by artillery in Zinjibar and nearby Qut that left 23 dead, including Pakistani and Somalian nationals.
Also, fighting in the town of Jaar left 10 al-Qaeda fighters dead or wounded, military officials said. They spoke on condition of anonymity because they were not authorized to speak to reporters.
To the east of Zinjibar, four al-Qaeda extremists were killed and one wounded while preparing a car bomb in the coastal town of Shaqra, an official said.
On Monday, two suicide bombers tried to hit army barracks and checkpoints in the same town in an attempt to stop the military from advancing in the south, killing four army-allied militiamen. Al-Qaeda has increasingly used suicide bombers and car bombs to try to halt the military offensive in the south, which started escalating May 12.
Al-Qaeda-linked extremists took advantage of Yemen's political turmoil last year to seize broad swaths of territory in the south. The network's branch in Yemen, known as al-Qaeda in the Arabian Peninsula, was behind the failed Christmas 2009 attempt to bomb an American airliner and other attempted attacks.