"While Hezbollah's actions are deplorable, and Israel has a right to defend itself, the excessive use of force is to be condemned," Annan told a Security Council meeting, adding that the radical Islamist group had made its countrymen hostages to its policy, and put the entire Middle East settlement process at risk.
The abduction of two Israeli servicemen by Hizbollah nine days ago triggered the ongoing Israeli military operation against Lebanon. Air attacks have since destroyed almost all bridges, roads and other infrastructure in Beirut and southern Lebanon, hampering evacuation and relief efforts.
Annan demanded that Hizbollah and radical groups in Palestinian Gaza release the abducted Israeli soldiers.
Lebanon's prime minister has said more than 300 have been killed hundreds of thousands have been forced to flee the country. Israeli casualties from attacks mounted by Hizbollah have been put at over 30.
Annan's statement echoes Russia's position on the Middle East conflict.
Russia's Foreign Ministry said in a statement Thursday that the scale of destruction caused in Lebanon by the Israeli military had gone far beyond Israel's stated goals of releasing its captured soldiers and curbing Hizbollah's militant activities.
"Moscow confirms its commitment to a decisive war against terrorism in all its forms and manifestations. We also confirm our demands that that the captured Israeli servicemen be unconditionally freed. However, the unprecedented scale of fatalities and destruction shows that actions [on the part of Israel] to achieve this goal have gone far beyond the bounds of an anti-terrorist operation."