A leading Israeli software company was forced to abandon plans to buy a smaller US rival Thursday in a $225 million deal because of national security objections by the Bush administration. Check Point Software Technologies Ltd. in Ramat Gan, Israel, formally withdrew its proposal Thursday near the conclusion of a rare, full-blown investigation by a US review panel over the company's plans to buy a smaller rival. Check Point had been told US officials feared the transaction could endanger some of government's most sensitive computer systems. Lawyers for Check Point offered to attach conditions to the sale that executives believed were onerous but were intended to satisfy the concerns expressed by the review panel, the Committee on Foreign Investments in the United States, said one person familiar with the process. But no agreement could be reached.