"I would like to discuss the ways to prevent Iran from getting nuclear weapons capability," Netanyahu said in brief public remarks with Merkel at his side at the start of her two-day trip. "I believe that this is the greatest challenge to the security of the world."
Speaking to his cabinet a day earlier, Netanyahu said Germany and other world powers negotiating with Iran needed to take a hard line with the Islamic republic to ensure it cannot "produce or launch nuclear weapons".
Tehran denies it is seeking the capability to make a nuclear bomb.
Merkel, who was accompanied by a high-level, 16-member, German delegation, said she hoped to help find a way to advance Israeli-Palestinian peace talks.
U.S. Secretary of State John Kerry has for months been trying to nudge both sides at least to agree on a framework deal by the end of April, although months of negotiations have made little visible progress.
"We want progress in these talks - I personally want that as well," Merkel said.
Both leaders said they would discuss ways to strengthen already close ties between their countries.