A majority of Dutch MPs have backed a motion calling on the government to consider taking steps against Israel, if it presses ahead with plans to annex part of the Palestinian West Bank.

The motion, drawn up by the Socialists, Labour and GroenLinks, and backed by two of the four coalition parties, calls on the government to prepare an inventory of possible measures which can be implemented if the annexation proceeds.

The wide backing for action is unusual in the Netherlands, which is usually supportive of Israel.

Israeli premier Benjamin Netanyahu has been mooting starting the process as early as Wednesday but faces mounting opposition from abroad, including from normally supportive countries.

An Israeli cabinet minister told Israel’s Army Radio that officials were still working out the final details with their US counterparts and the move, which will give Israel control of 30% of the West Bank, will be made later this month, the Guardian reported.

The Liberal democratic party D66 and the Christian Democrats both support the opposition parties motion. The ruling VVD says annexation by Israel would be illegal and must be prevented, but said the motion is ‘undiplomatic’.