Last month, head of the Palestinian Authority Mahmoud Abbas stated that they had terminated all their agreements with Israel and the US amid Tel Aviv's intention to extend its sovereignty over parts of the West Bank.

Palestinian Prime Minister Mohammed Shtayyeh has warned that if Israel extends its sovereignty over West Bank areas, the Palestinians will unilaterally declare a state based on the pre-1967 lines.

Speaking to reporters in Ramallah on Tuesday, Shtayyeh described Israel’s sovereignty extension drive as an "existential threat" to the Palestinians and a serious violation of Tel Aviv’s agreements with the Palestinian Authority (PA).

He spoke as Hussein al-Sheikh, a senior aide to Palestinian President Mahmoud Abbas, said in an interview with The New York Times that “we don’t want things to reach a point of no return” and that Tel Aviv’s West Bank-related sovereignty extension “means no return in the relationship with Israel”.

“Either they backtrack on annexation and things go back to how they were, or they follow through with annexation and they go back to being the occupying power in the whole West Bank”, al-Sheikh pointed out.

He said that Israel would have to “take full responsibility” for the repercussions of the move, adding that “it could go back to like it was before Oslo”, in an apparent nod to the 1993 Oslo Agreement which established the PA and gave it limited powers. 

The remarks came after the Palestinian movement Hamas, which controls the Gaza Strip, cautioned on Monday that Israel’s sovereignty extension “will be doomed to failure and its conspiracies will not secure a future for its existence on the Palestinian land".

The warning followed Mahmoud Abbas telling Al Jazeera in May that the PA "has discharged all obligations under all agreements with the governments of the United States and Israel, including those related to security”.

This was preceded by Israel’s Prime Minister Benjamin Netanyahu and his main political rival, Benny Gantz, clinching a coalition deal in April which stipulates that the Israeli government can start considering the implementation of the West Bank-related extension of sovereignty as of 1 July, in line with US President Donald Trump's Middle East plan.

Earlier, US Ambassador to Israel David Friedman announced that the Trump administration was ready to recognise Israel’s extension of sovereignty over 30 percent of the West Bank.

Trump’s Middle East Peace Plan  

Trump revealed his Middle East blueprint in late January, touting it as the "deal of the century". The plan, in particular, envisaged an extension of Israeli sovereignty over the West Bank and the Jordan Valley, as well as the recognition of Jerusalem as the "sovereign capital of the State of Israel" and that it should remain an undivided city.

The blueprint prompted harsh criticism from Abbas, who has repeatedly insisted on restoring the pre-1967 borders of the Palestinian lands.

Israel has for decades been embroiled in a conflict with the Palestinians, who are seeking diplomatic recognition as an independent state on the territories of the West Bank, which were occupied by the Jewish state during the Six-Day War in 1967.