The foreign minister of the Hamas-led Palestinian government has dismissed a threatened referendum on a two-state solution to the conflict with Israel.
Zahhar walked out of the conference, but may attend bilateral talks
Mahmoud Zahhar insisted the vote would be a waste of time and his cash-starved administration had no funds to hold it.
"Nobody can trust Israel... Nobody will recognise Israel," he said in Malaysia.
Earlier, he left a Non Aligned Movement meeting in protest at the presence of a top member of Fatah, the rival faction which proposed the referendum.
"I can't stand side by side with a man who is not representing the Palestinian government. He is playing a dirty game," Mr Zahhar said.
He was referring to senior Fatah official Farouk Kaddoumi, who had presented himself as head of the Palestinian delegation and added insult to injury by announcing he intended to "train" Mr Zahhar in diplomacy.
Last week, Palestinian Authority President Mahmoud Abbas, gave Hamas 10 days to adopt an 18-point programme agreed by various faction members jailed by Israel - or he would instigate a referendum.
The plan includes recognition of Israel and acceptance of a two-state solution as the basis for a peace deal.
Mr Zahhar laughed when asked to comment on the plan, saying: "Nobody will recognise Israel. There is no need for a referendum... The people will give to him our answer."
He added that Hamas - which advocates the destruction of Israel - was not afraid of a vote, but said it was a waste of time and a waste of money when the government had no money.
He also dismissed international demands led by the US for Hamas to soften its anti-Israeli stance, by renouncing violence and recognising the Jewish state.
"What type of moderate system would America like? To accept the occupation of our land and annexation of Jerusalem?" he said.
And he called Mr Abbas's goal of a negotiated two-state deal, with Israeli withdrawing from all the land occupied in the 1967 war, "unrealistic".
"He is believing in political methods which, from our point of view, are unable to be implemented."
Mr Kaddoumi arrived in Putrajaya as representative of the umbrella Palestine Liberation Organisation, in which Fatah is the dominant faction but which Hamas has refused to join.
The Fatah veteran, who lives in exile in Tunis, told reporters: "I have had 30 years of experience. This is the first day he is coming to such a conference.
"I told him, I would train you and then I will turn over the whole process to you. And you be the minister of foreign affairs."
The BBC's Jonathan Kent in Kuala Lumpur where the conference is being held, said Mr Zahhar appeared less than impressed at the comments.
Malaysia's foreign minister, Syed Hamid Albar, attempted to play down the row and said Mr Zahhar would be attending "bilateral" meetings at the gathering of 116 developing nations.
The militant Islamic Hamas movement came to power after winning Palestinian parliamentary elections in January.
The government has been isolated diplomatically and financially by Israel's allies for its refusal to renounce violence and recognise the Jewish state. Tension has also been increasing between Hamas and Fatah, the former ruling party.