A leaked report by a former UN envoy says the international Quartet on the Middle East has become irrelevant and the UN should abandon it.
Alvaro De Soto's report was meant to be confidential
Alvaro de Soto said UN regional policy has failed because of its subservience to US and Israeli concerns.
He said that the US, European Union and Israeli boycott on Hamas had had devastating consequences.
UN Secretary General Ban Ki-moon has said that the report represented Mr De Soto's personal views.
He disputed his former envoy's conclusion that the Quartet had become a "side-show" and that the UN should pull out of it.
Mr De Soto had been the UN envoy to the Middle East for two year until his resignation in May. His report was a confidential end-of-mission statement, not intended for publication.
The leaked report emerged earlier this week. The BBC received a copy on Thursday.
Mr De Soto is a Peruvian diplomat who has worked for the UN in El Salvador, Cyprus and the Western Sahara.
He is to be replaced by the UK's Michael Williams.
Mr De Soto indicated he left his post because he was frustrated that he was being ignored.
His main complaint concerns the dealings of the Quartet, made up of the US, Russia, the EU and the UN, with the Palestinians and the Israelis.
"Even-handedness has been pummelled into submission in an unprecedented way.
"The steps taken by the international community with the presumed purpose of bringing about a Palestinian entity that will live in peace with its neighbour Israel have had precisely the opposite effect," Mr De Soto wrote.
"The Quartet took all pressure off Israel. With all the focus on the failings of Hamas, the Israeli settlement enterprise and barrier construction has continued unabated."
He blamed the "tendency that exists among US policy-makers... to cower before any hint of Israeli displeasure and to pander shamelessly before Israeli-linked audiences".
He said that Israeli policies seemed "perversely designed to encourage the continued action by Palestinian militants".
Mr De Soto also criticised the Palestinian leadership.
He describes as "abominable" Hamas's commitment to the destruction of Israel. Palestinian efforts to stop militant attacks are "patchy at best, reprehensible at worst".
He argued that the US, EU and Israeli decision to boycott and cut off funds to the Hamas-led government was a strategically disastrous one in humanitarian terms and in terms of fatally weakening Palestinian institutions and the ability of the authorities to maintain order.