US envoy George Mitchell was to meet Israeli Prime Minister Benjamin Netanyahu on Friday at a time when hopes of restarting the Middle East peace process appeared dimmer than ever. Mitchell was to meet the hawkish premier in Jerusalem on Friday morning, and hold talks with Palestinian president Mahmud Abbas later in the day in Ramallah, the political capital of the Israeli-occupied West Bank. US President Barack Obama's Middle East envoy was unlikely to achieve a breakthrough as even Israel has insisted the world should give up the notion that a comprehensive solution to the decades-old conflict would be found anytime soon. Mitchell did his best to appear upbeat, saying on Thursday every effort would be made to relaunch negotiations. The US administration is seeking a comprehensive deal that would see Israel strike peace agreements with the Palestinians, Syria and Lebanon and normalise relations with Arab states. But Obama's call for a complete freeze of Israeli settlement construction in the occupied West Bank encountered stiff opposition from Netanyahu's government. 'In this government's thinking, efforts at negotiations with the Palestinians have been set back because of the exaggerated US demands on settlement, and the reality on the ground has grown more tense in the interim,' the English-language Jerusalem Post said in an editorial on Friday. Israel's hardline Foreign Minister Avigdor Lieberman made it bluntly clear a comprehensive peace accord with the Palestinians was not within reach. 'Those who think that we can within the coming years reach a global deal that will end the conflict do not understand reality. They are sowing illusions,' Lieberman told public radio on Thursday. 'We have to be realistic -- we will not be able to reach agreement on core and emotional subjects like Jerusalem and the right of return,' he said. 'What we have to do is to reach a long-term agreement and delay the difficult subjects for later. Defence Minister Ehud Barak was less pessimistic, saying after talks with Mitchell on Thursday that 'no obstacle is insurmountable.' Mitchell, who played a key role in the 1998 Good Friday peace deal in Northern Ireland, has been spearheading Obama's efforts to get Israel and Palestinians to relaunch peace talks that were suspended in late December after the Gaza war broke out. At a three-way summit on the sidelines of the UN General Assembly in late September, Obama told Netanyahu and Abbas to stop dragging their feet. Since then, Israelis and Palestinians have traded accusations over who was responsible for stoking tensions that have led to sporadic clashes over access to the Al-Aqsa mosque compound, a flashpoint site holy to Muslims and Jews in the Old City of Jerusalem. And Abbas has come under a hail of criticism from among Palestinians and across the Arab world for apparently caving in to US pressure in agreeing not to press for a vote at the UN Human Rights Council on a damning UN report on the Gaza war. Abbas has since backtracked, but the furore makes it difficult for him to make concessions to the United States and Israel, political analysts say. 