An Israeli naval officer holds the mooring rope of an INS Tanin, a Dolphin AIP class submarine, during a ceremony upon its arrival at a naval base in the northern Israeli city of Haifa, on Sept. 23, 2014. The Israeli Navy welcomed the newest addition to its submarine fleet, INS Tanin, a fourth German-made vessel that military and defense officials say will dramatically boost Israel's ability to operate against foes near and far, local media reported. (Xinhua/POOL/Amir Cohen)

BERLIN, Oct. 23 (Xinhua) -- The German government has approved the controversial sale of three military submarines to Israel following a month-long delay on Monday.

Chancellor Angela Merkel's official spokesperson, Steffen Seibert, told press that Germany would sign an official treaty detailing the confidential level of government subsidies offered in the arms sale by Berlin later on Monday.

According to reports, Germany has agreed to cover up to a third of the total cost of 1.5 billion euros (1.8 billion U.S. dollars) out of a historical sense of responsibility for Israel's security.

The sum would amount to "540 million euros at most" spread across several federal budgets between 2018 and 2027, Seibert was quoted saying.

The sale of three submarines by the Kiel-based defense manufacturer Thyssen Krupp Marine Systems became the subject of media speculation after it was temporarily halted by the German government on suspicion of corruption.

However, "all relevant perspectives," including ongoing investigations by Israeli authorities, have now been considered in the agreement.