German Chancellor Angela Merkel said Thursday that "indirect talks" with armed Islamist group Hamas were essential to advancing efforts toward a Middle East ceasefire.

"Of course there must be indirect talks with Hamas," Merkel told a forum on Europe, noting that Egypt and other Arab countries were already trying to mediate between Israel and the Gaza Strip's Islamist rulers.

"Of course Hamas has to be included because without Hamas there will be no ceasefire."

Merkel was speaking as her foreign minister, Heiko Maas, began a one-day diplomatic mission to the region.  

He spoke with Israeli officials and was also due to meet Palestinian president Mahmud Abbas in Ramallah in the occupied West Bank. But the German minister had no plans to meet with Hamas, which the European Union considers a terrorist organisation.

His visit was part of stepped up efforts toward a ceasefire to stem 10 days of deadly violence between Israel and armed Palestinian groups in Gaza.

Egypt has sought to mediate a ceasefire between Hamas and Israel since the deadly violence erupted on May 10.

Merkel called Cairo "a very very important major player in every issue when it comes to whether there will be a ceasefire".