Mousa Abu Marzouk, the deputy head of Hamas' political bureau, also said on Tuesday that Israel's policy of assassinating the group's senior officials in Gaza was aimed at preventing Hamas candidates from participating in the January Palestinian parliamentary elections.
"This policy is not new. Israel is moving at various levels against Hamas to prevent it from taking part in the coming elections in order to bring in a Palestinian authority of its own design," Abu Marzouk told journalists in Damascus.
He added that the Israeli campaign against Hamas was part of an "internal political struggle" between Sharon and his main rival, Benjamin Netanyahu, for the leadership of the Likud Party on the one hand, and "fears of a Hamas victory" in the elections on the other hand.
Abu Marzouk also complained that Gaza lacks sovereignty despite Israel's withdrawal two weeks ago, which ended a 38-year occupation of the coastal strip.
"Israel is still controlling its [Gaza's] airspace, sea and crossings and imposes its sovereignty on it," he said. Abu Marzouk's comments came after days of violence in the Gaza Strip.
Despite Hamas' declaration that it would halt rocket attacks on Israeli towns, Israel has pressed ahead with its large-scale offensive against Palestinian fighters.
Israeli Defence Minister Shaul Mofaz said the army would pound resistance fighters relentlessly to force them to stop firing rockets at Israeli towns.
Israel arrested 82 Palestinians in the West Bank early on Tuesday, adding to the 297 arrested in recent days, the Israeli military said.
The new violence started after a blast Friday at a Hamas rally in Gaza's Jebaliya refugee camp killed 21 people. Hamas said Israeli aircraft had fired missiles into the crowd which Israel denied.