 He argues that Alexander's chancellor Ammonius should be seen as a Ptolemaic agent.There is however no explicit evidence for this, and Boris Chrubasik presents Alexander's initial successes as accomplished without any Ptolemaic involvement, and challenges the identification of Ammonius as an Egyptian in particular.At any rate, an agreement between the kings was sealed in 150 BC, when Ptolemy VI married his teenage daughter Cleopatra Thea to Alexander in a ceremony at Ptolemais Akko.