The Israeli Navy is reportedly close to finalizing a deal to buy three nuclear-capable submarines from Germany for $1.3 billion.

The purchase of the submarines is expected be finalized next month in Berlin and will upgrade Israel’s existing nearly 20-year-old submarine fleet, Maariv reported.

“The new submarines are said to be more advanced, longer and equipped with better accessories,” the report said.

The Israeli Navy’s Dolphin-class submarines provide the Jewish state with second-strike nuclear capabilities, experts say. They have the ability to travel long distances from Israel’s territorial waters and can reportedly carry long-range cruise missiles tipped with nuclear warheads.

Israel has already purchased five nuclear-capable Dolphin-class submarines from Germany with a sixth sub due for delivery in 2017.