[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2009/images/01/06/art.getty.palestine.protest.jpg caption="An audio message says that Israeli airstrikes in Gaza are a gift from President-elect Barack Obama."](CNN) - An audio message reportedly from al Qaeda's deputy chief vows revenge for Israel's air and ground assault on Gaza and calls the Jewish state's actions against Hamas militants "a gift" from President-elect Barack Obama.
The speaker, identified as Ayman al-Zawahiri, addresses Muslims in Gaza, stating that the violence "is one part of a series of a crusade war against Islam and these airstrikes are a gift from Obama before he takes office."
The message, posted on various Islamist Web sites Tuesday, urges militants to rally against Israel.
"My Muslim brothers and mujahedeens in Gaza and all over Palestine, with the help of God we are with you in the battle, we will direct our strikes against the crusader Jewish coalition wherever we can."
The 10-minute message moves on to address Muslims worldwide, claiming that Obama was portrayed as "the savior who will come and change American policy" during the U.S. election but is now "killing your brothers and sisters in Gaza without mercy or even pity."
Obama's transition team did not immediately respond to the message. Earlier Tuesday, the president-elect said he is "deeply concerned" about the loss of life in Gaza and Israel and promised to make the issue a top priority in his administration.