Germany's foreign minister said on Thursday that Israel was increasingly isolated diplomatically over the humanitarian crisis in Gaza and the push by some countries to recognise a Palestinian state.

Johann Wadephul said in a statement before heading to Israel that the recent UN conference on a two-state solution to the Israeli-Palestinian conflict, which was boycotted by the US and Israel, showed that "Israel is finding itself increasingly in the minority".

Germany is one of Israel's staunchest diplomatic allies but Wadephul noted that "in view of the open threats of annexation by some in the Israeli government, a growing number of European countries are ready to recognise a state of Palestine without previous negotiations".

Last week more than 70 Israeli lawmakers, including some in Prime Minister Benjamin Netanyahu's right-wing coalition, passed a motion urging the government to impose sovereignty over the occupied West Bank.

Wadephul repeated Berlin's position that "the recognition of a Palestinian state should come at the end of the process" of negotiations.

He did however sharpen his tone slightly by insisting that "this process must begin now" and that "Germany will also be forced to react to unilateral moves".

On Gaza, whose two-million-plus inhabitants now face an unfolding famine, Wadephul demanded that Israel enable more aid into the territory "immediately, comprehensively and in a lasting way" to alleviate the "dramatic" situation there.

Wadephul is expected to meet his Israeli counterpart Gideon Saar and President Isaac Herzog on the trip to Israel, as well as Netanyahu. (AFP)