A Hamas spokesman said on Friday that Prime Minister Benjamin Netanyahu's decision to toughen the conditions of Palestinian security prisoners in Israeli prisons constitutes a violation of international law.

Hamas spokesman Sami Abu Zuhri said that Netanyahu's decision was an attempt to cover up his government's failure to secure the release of captured IDF soldier Gilad Shalit.

"Israel has failed to reach the captured IDF soldier," Abu Zuhri said. "Netanyahu is responsible for Shalit not having been returned. [Shalit] will only be returned in exchange for Palestinian prisoners."

Abu Zahri also called on the international communityto "act against the activities of the occupation."

On Thursday, Netanyahu announced that he plans on toughening the conditions of Palestinian security prisoners in Israeli prisons.

"I have decided to change Israel's treatment of terrorists sitting in prison," Netanyahu said during the closing statements at the Presidential Conference in Jerusalem. "We will give them all that they deserve according to international law but nothing beyond that."

Netanyahu said that he is required to respect Israeli law, international law, and international trust but nothing beyond that, so Israel is taking a series of steps to change prisoners' conditions.

"We will stop, among other things, the absurd practice in which terrorists who murdered innocent people enroll in academic studies," he said. "There will be no more 'doctors of terror' - the celebration is over."

Netanyahu's comments come after Hamas refused Thursday to answer the International Red Cross' request that Hamas provide proof that Shalit is still alive.