Mahmoud Abbas said he hoped to start a "national dialogue" in the next few days that could lead the Hamas government "to amend its platform" and conform with commitments to the peace process made by the previous Palestinian administration.
"Our approach needs the support of the international community," Abbas told members of the European Parliament in Strasbourg, France on Tuesday.
"The new government must be given the chance to adapt to the basic requirements of the international community."
The EU and the United States froze hundreds of millions of dollars in direct aid to the Palestinian government after the militant group Hamas won legislative elections in January.
Washington and the EU list Hamas as a terrorist organisation and have demanded that the group renounce violence, recognise Israel and abide by previous peace treaties signed with Israel.
"The new government must be given the chance to adapt to the basic requirements of the international community"
Abbas told the EU assembly that "stopping assistance to the Palestinian Authority, cutting aid, will exacerbate the deteriorating economic and social situation."
He said the cuts left the Palestinians facing a "humanitarian catastrophe."
'Tension and conflict'
He also warned of dire consequences if the Israeli government goes ahead with plans to impose borders on the Palestinians.
External aid cuts have hit
thousands of Palestinians hard
"The attempt to implement these unilateral projects will destroy any remaining hope of reviving the peace process," Abbas said.
"It will also lead to another bitter era of tension and conflict for which peoples in this region have, for decades, paid a heavy price."
Israel has said it will redraw its borders with the occupied West Bank and siphon off the largest Jewish settlements built on Arab land with or without agreement from the Palestinians.
The European Union meanwhile says it is moving ahead with plans to get financial aid to Palestinians, without it reaching the Hamas government.
External Relations Commissioner Benita Ferrero-Waldner said a temporary trust fund to handle the money could be set up as early as June.
But she said that the new aid mechanism needed Israel's support and the resumption of transfer of more than $50 million in monthly tax revenues it collects on behalf of the Palestinians.
The aid cutoff has plunged the West Bank and Gaza into a financial crisis.
To try to get around Hamas, the EU and its three partners in the so-called Quartet of Middle East negotiators - Russia, the United States and the United Nations - decided last week to try to funnel aid through a temporary trust fund.
"Even if there is a government that does not meet international requirements, you should not punish the people"
Abbas welcomed that decision.
"I would like the mechanism approved by the Quartet last week implemented as soon as possible so we can avoid this catastrophe," Abbas told a news conference after his speech.
The fund would be held by an international organisation such as the World Bank, the International Monetary Fund or the UN and jointly controlled by the Quartet members to avoid direct contact with Hamas.
Abbas said a prolonged suspension of international aid and Israeli tax transfers would leave 165,000 public sector workers without salaries in Gaza and the West Bank.
"Life will be frozen and then there will be an explosion of anger and this would lead to a chaotic situation of which we cannot foresee the results," he said.
"Don't allow the Palestinian people to reach such a level," he added in an appeal to the EU.
"Even if there is a government that does not meet international requirements, you should not punish the people."
Abbas, whose Fatah party was defeated in the January elections, has been prodding the new Hamas government to change its anti-Israel position.
Hamas has said it will recognise Israel only if all Palestinian prisoners are freed, territories seized by the Jewish State in 1967 are returned, and refugees that fled and were expelled from their homes in 1948 and 1967 are allowed to go back.
It is unlikely, however, that Israel will accept such demands as it fears refugees returning to lands that are mostly located in modern day Israel will tilt the demographic balance in favour of the Palestinians.