A senior Palestinian official Monday condemned the participation of US envoys in an event linked to Israeli settlers and scoffed at their account that it was for a new archaeology project.
US ambassador to Israel David Friedman and White House adviser Jason Greenblatt were among US officials attending the event organised by the City of David Foundation on Sunday night in Israeli-annexed east Jerusalem.
They helped open what organisers say is an ancient pilgrimage road, now underground in a tunnel, leading to the second Jewish temple some 2,000 years ago.
The tunnel, in a highly sensitive area next to Jerusalem's Old City, passes underneath homes in the Palestinian neighbourhood of Silwan.
Palestinians and anti-occupation activists see it as another attempt by Israel to cement its control over predominantly Palestinian east Jerusalem.
Saeb Erekat, the chief Palestinian negotiator, said he believed the tunnel was a project being used by Israeli right-wingers to further Israel's claim on east Jerusalem and advance settlement growth there.
"It has nothing to do with religion, it is fake," he told journalists at his office in Ramallah in the occupied West Bank.
He added: "It's a settlement project. It's based on a lie that has nothing to do with history.
"This is a disgrace to any diplomat, to undermine the two-state solution, to undermine the fact that there will never be peace without east Jerusalem being the capital of Palestine."
Erakat cited reports by two Israeli NGOs questioning the archaeological methods used.
One of the organisations, Peace Now, also says cracks emerged in multiple houses in Silwan after the digging began.
The other, Emek Shaveh, said "the use of archaeology by Israel and the settlers as a political tool is a part of a strategy to shape the historic city and unilaterally entrench Israeli sovereignty over ancient Jerusalem."