Washington/ Tokyo: The United States warned the new Hamas government on Monday that any sponsorship of terrorism by Palestinian officials would further isolate them, after a Palestinian suicide bomber killed at least nine people in Tel Aviv.
In condemning the bombing that also wounded 60 people outside a restaurant in the seaside city, the White House told the Palestinian Authority it was responsible for preventing such attacks.
UN Secretary General Kofi Annan criticised the bombing as "unjustifiable" and also urged the Hamas-led Palestinian government to do the same.
"(Annan) calls on the Palestinian Authority to take a clear public stand against such unjustifiable acts of terrorism, noting that President (Mahmoud) Abbas has done so and regretting that the new government has not," his spokesman, Stephane Dujarric, said in a statement.
Abbas earlier condemned what he called an act of terrorism, while Palestinian militant group Hamas, which recently formed a new government following its January election victory, laid the blame at Israel's door, calling it a natural consequence of country's "aggression".
Hamas took control of the Authority three weeks ago after winning elections in January.
State Department spokesman Sean McCormack said the bombing showed the "true nature" of a Hamas-led government, which he said encouraged violence by condoning the attack.
"They would rather encourage 16-year-olds to go out, strap explosives to them and go out and try to kill other 16-year-olds, other innocent civilians. That's the kind of government that you're dealing with," McCormack said.
The White House also had strong words for Hamas.
"Defense or sponsorship of terrorist acts by officials of the Palestinian cabinet will have the gravest effects on relations between the Palestinian Authority and all states seeking peace in the Middle East," spokesman Scott McClellan said.
A Palestinian government that encouraged or tolerated terrorism would harm Palestinian interests and "ensure its own further isolation," he said.
"We reiterate that the United States will have no contact with such a government and we call upon all states to demand that it abandon its support for terror," McClellan said.
Meanwhile, on Tuesday,Japan has decided to halt new aid to Palestinians via the Hamas-led Palestinian Authority until it becomes clear that Hamas is committed to the Mideast peace process, Foreign Ministry officials said.
Japan - which has given $840 million in aid to Palestinians since 1993 - will however continue to offer fresh humanitarian aid if the need arises, said Akira Chiba, assistant press secretary for the Japanese Foreign Ministry.
"Our stance is that we want to see whether it (Hamas) will adopt peaceful measures and participate in the peace process," Chiba said.
"Until we have a clearer picture ... there won't be a situation where new aid would be given," Chiba said.
Another Foreign Ministry official said that while Japan had stopped offering new aid, it planned to continue pre-existing aid projects, such as repairing roads and building residential homes.