FRANKFURT—The foreign ministers of France, the U.K. and Germany on Saturday urged Palestine and Isreal to return to the cease-fire after a renewed outbreak of fights between the two sides.

"We're very concerned about the reigniting violence in the Gaza Strip," Laurent Fabius, Philipp Hammond and Frank-Walter Steinmeier said in a joint statement. They added "both parties" need to take the necessary steps to meet pressing humanitarian needs and enable access to aid.

The statement comes after Israelis and Palestinian militants exchanged bomb and rocket attacks on Saturday, with Palestinian militants in Gaza firing 27 rockets at Israel in the first 17 hours of Friday. Israel struck 47 targets in the coastal enclave, mostly from manned fighter jets and drones, the Israeli military said. The new fighting follows a three-day cease-fire that lapsed on Friday morning as Israel and Hamas failed to reach an agreement in Cairo on an extension of the truce during talks.

The foreign ministers said they are backing the current Egyptian-led efforts without elaborating further. They instead said that Israeli security interests and Palestinian demands for an end of the blockade have to be met to ensure an enduring cease-fire. "The priority goal has to be to return to talks over a two- nation solution, which is the only way to solve the conflict and to end the humanitarian suffering for good," they said.

Write to Eyk Henning at eyk.henning@wsj.com