The United Nations said Israel has agreed to again allow imports of construction materials into the Gaza Strip after a two-month clampdown.

Israel restricted items that can enter Gaza since the militant Hamas group seized the coastal strip in 2007, fearing Palestinian militants could use materials like metal and concrete for military purposes.

In 2010, Israel eased the restrictions to allow imports for internationally supervised projects. But in October, it halted the entry of all construction materials after discovering a concrete-lined tunnel along the border built by Palestinian militants.

UN Mideast envoy Robert Serry said Monday the materials will be used to build schools, housing and sanitation facilities.

Critics say Israel's policy is tantamount to collective punishment and that ordinary Gazans suffer.

Israeli officials were not immediately available for comment.