The Church of England's General Synod last week voted to disinvest in companies profiting from the Israeli occupation of Palestinian territories.
The Archbishop of Canterbury, the Rt Rev Rowan Williams, voted for the motion, which urged disinvestment from companies such as the US construction equipment firm Caterpillar.
Caterpillar has been targeted for supplying Israel with bulldozers that have been used to destroy Palestinian homes. The church owns an estimated £2.2m worth of shares in the company.
The vote contradicts the position taken by the church's ethical investment advisory committee, which has concluded that disinvestment in Caterpillar is not justified.
However, it is far from clear whether any disinvestment will actually take place. The Church of England's investment decisions are made by the Church Commissioners, the Church of England Pensions Board and the CBF Church Fund - not the Synod.
"The Synod doesn't have the power to tell the advisory group what to do, and the advisory group doesn't have the power to tell the investors what to do," said a spokesman. "But it's not something you treat lightly."
War on Want, which has campaigned on the issue, welcomed the vote. "It vindicates the serious concerns we have about the use of Caterpillar machines in the human rights violations being perpetrated by the Israeli army," said Nick Dearden, campaigns officer for the charity.
"We now call on the Church Commissioners to enforce the Synod's decision and send a clear message that companies such as Caterpillar have a responsibility to ensure their products are not used to violate human rights."
The church spokesman said it was impossible to say whether the advisory committee would change its position. "It will be close to the top of the agenda at its next meeting," he said.