Donald Trump won the U.S. presidential election last November partly due to the support given him by evangelical Christians. However, not all Christians are backing him up as he prepares to take over the White House.

The National Council of Churches and several other Christian organisations have expressed "grave concerns" over his leadership and are already opposing some of his stated policies as well as his planned Cabinet and other appointments.

"We urge President-elect Donald Trump, who has said he shares our Christian faith, to take seriously his responsibility to bring our nation together and to heed the oath he will take to preserve, protect and defend America," the groups said in a statement released on Jan. 6, according to Religion News Service.

The statement — which was also signed by the Conference of National Black Churches, Ecumenical Poverty Initiative, and Samuel DeWitt Proctor Conference — implored Trump to start working before his oath of office by making revisions to his policy agenda and political appointments.

Among the policy items that "would put the most vulnerable among us in jeopardy," according to the Christian groups, is his promise to repeal the Affordable Care Act, better known as Obamacare. Should Trump really make good on his promise, they said he should already have a ready replacement that would care for the poor and vulnerable in America.

"Repealing it without simultaneously offering a replacement is reckless and unnecessarily endangers the health of millions of people. This is certainly no way to make America great," they said.

Another thing they are "deeply troubled" with is Trump's expected appointment of Sen. Jeff Sessions as attorney general, Stephen Bannon as his chief strategist, and Michael Flynn as national security adviser.

"These objectionable nominees represent a bygone era of hatred that we have denounced and worked tirelessly to eradicate," they said. "Their corrupted credentials, which include condoning and supporting racist, anti-Semitic, white supremacist, xenophobic, and anti-Muslim ideologies, are not only unacceptable but they should disqualify them for service as public officials."