The Israeli government is seeking to renege on a pledge to demolish a West Bank outpost built on privately owned Palestinian land.

The move comes amid a wave of international condemnation over its retrospective authorisation this week of three other illegal outposts, strengthening Israel's hold on the West Bank and bolstering pro-settler groups, whose influence on government policy is growing.

The attorney general, Yehuda Weinstein, will ask the supreme court to delay an order to evacuate and demolish five apartment buildings at Ulpana, on the edge of the Beit El settlement. The case is due to be heard before Tuesday's deadline for evacuation.

The government had earlier given a commitment to carry out the order, saying it did not approve settlement construction on private land. Most settlements in the West Bank are built on land taken over by the state of Israel during its 45-year occupation.

But vigorous lobbying – including threats to bring down the coalition – by pro-settler members of the ruling Likud party, smaller rightwing parties and government ministers led prime minister Binyamin Netanyahu to seek ways to avoid confrontation on the issue.

Three outposts, which were defined "illegal" because they lacked proper authorisation when founded in the 1990s, were retrospectively "legalised" this week by a special ministerial committee. Under international law, all settlements on occupied territory are illegal.

Critics said the move was, in effect, the first official establishment of new settlements in the West Bank in more than two decades.

The decision drew criticism from the US, UK, French, German, Danish and Jordanian governments, the European Union, the United Nations and the Palestinian Authority.

The British foreign secretary, William Hague, said "designating outposts as settlements... sets a dangerous precedent" and "risks sending the message that [Israel] is not serious about its stated commitment to the goal of a two-state solution to the Israeli-Palestinian conflict".

The outposts – Bruchin, Rechelim and Sansana, which are home to 830 people – are among about 100 unauthorised developments in the West Bank. Israel has repeatedly made commitments to the international community to dismantle them, though critics now fear they too could now be in line for legal protection.

Ulpana, a collection of small apartment blocks, five of which are under a demolition order, has been the subject of an intense lobbying campaign over recent weeks.

Scores of politicians, including cabinet ministers, have visited Ulpana to pledge opposition to the supreme court order. Moshe Yaalon, minister for strategic affairs, warned at the weekend: "We said we wouldn't evacuate the neighbourhood. Should this happen, the government will fall."

The occupants of the apartments, built 12 years ago, say the land was bought from its Palestinian owner, a claim rejected by the court.

They say the then Israeli government, headed by Ehud Barak, now defence minister, encouraged the development. "They gave people money to come and live here," said resident Harel Cohen. "The government supplied all the infrastructure – gas, electricity, roads. It was the agenda of the government that this neighbourhood will be built. No one here thinks we will be evacuated."

Ironically, Barak is the strongest voice in the present cabinet behind compliance with the court order, a stance which has led to calls by colleagues for him to be sacked.

The campaign over these four outposts – and another, Migron, due to be evacuated by 1 August after repeated delays – is an indication of the likely resistance to an Israeli-Palestinian agreement on borders which would require the removal of tens of thousands of settlers from the land of a future Palestinian state.

About 350,000 Israelis live in West Bank settlements and outposts, and a further 200,000 in East Jerusalem. The issue of settlements is seen by the Palestinians and the international community as the main impediment to a peace agreement.