John Dugard, special rapporteur on human rights in the occupied Palestinian territories, said in a report to the UN Human Rights Commission on Wednesday that the Israeli-built separation wall was causing major humanitarian problems.
"The character of East Jerusalem is undergoing a major change as a result of the construction of the wall through Palestinian neighbourhoods," Dugard said.
"The clear purpose of the wall in the Jerusalem area is to reduce the number of Palestinians in the city by transferring them to the West Bank.
"This causes major humanitarian problems: Families are separated and access to hospitals, schools and the workplace are denied."
Dugard recalled that the wall between Israel and Palestinian territories - described by Israel as a security measure - had gone ahead despite a 2004 ruling by the International Court of Justice.
The report to the UN was immediately condemned by the Israeli UN envoy to the UN rights panel, who said the document was pursuing "manifest political ends".
Meanwhile, a report by the UN Office for the Co-ordination of Humanitarian Affairs, or OCHA, said the Israeli army had increased the number of roadblocks and barriers in the West Bank by 25% since last summer.
The number of road obstacles rose to 471 in January, from 376 last August at the time of Israel's Gaza pullout, OCHA said, and they tightened travel restrictions for Palestinians and made it harder for them to reach properties, markets and medical services.
Israel says its network of permanent checkpoints, concrete barriers and temporary mobile roadblocks are needed to protect Israeli towns and Jewish settlements from Palestinian attacks.