Israeli opposition figures and activists have warned that plans to curb the powers of the Supreme Court pose a serious threat to democracy.

The reforms unveiled by the new justice minister include enabling parliament to overrule the top court's decisions.

Critics say such a move will undermine the independence of the judiciary and could be used for political ends.

It follows the instalment last week of a new coalition government that is the most right-wing in Israeli history.

Under the plans announced by Justice Minister Yariv Levin on Wednesday evening, a simple majority in the Knesset (parliament) would have the power to effectively annul Supreme Court rulings. This could enable the government of the day to pass legislation without fear of it being struck down.

Critics fear that amongst other things, the new government could use this to scrap Prime Minister Benjamin Netanyahu's ongoing criminal trial, although the government has not said it would do that. Mr Netanyahu is being tried on charges of bribery, fraud and breach of trust - something he strongly denies.

The reforms would also give politicians more influence over the appointment of judges, with most members of the selection committee coming from the ruling coalition.

"We go to the polls, vote, choose, but time and time again people we didn't choose decide for us," said Mr Levin, alluding to the power of judges to overturn laws.

"The time has come to act."

If it passes into law, the plan could make it easier for the government to legislate in favour of Jewish settlements in the occupied West Bank without worrying about challenges in the Supreme Court. Israel has previously highlighted the power of the court to rule against it, as a way of blunting international criticism of such moves.

The proposed judicial reforms have drawn a fierce reaction from political opponents and civil society activists.

Opposition leader Yair Lapid, who was defeated by Mr Netanyahu in November's elections, said they amounted to "a unilateral revolution against the system of government in Israel".

The new government was "threatening to destroy the entire constitutional structure" of the state, he warned, vowing that he would reverse the reforms "the moment we return to power".

Mr Netanyahu's former coalition partner and alternate prime minister, Benny Gantz, said the reforms meant that Israel had "a government that with its majority controls the Knesset, and now together they will control the court."

The plans were announced a day before the Supreme Court heard a challenge against the appointment to Mr Netanyahu's cabinet of a would-be minister currently serving a suspended sentence for tax fraud. If the appeal is upheld, it could pave the way for a showdown between the court and the government.