Netanyahu says preventing nuclear Iran his primary challenge

Israel's Prime Minister Benjamin Netanyahu waves to supporters as he stands next to former foreign minister Avigdor Lieberman at the Likud party headquarters in Tel Aviv January 23, 2013.

TEL AVIV (Reuters) - Israeli Prime Minister Benjamin Netanyahu, in an election victory speech on Wednesday, said preventing a nuclear-armed Iran would be the primary challenge facing the new government he intends to form.

"I am proud to be your prime minister, and I thank you for giving me the opportunity, for the third time, to lead the state of Israel," he told a cheering crowd at the campaign headquarters of his right-wing Likud party.

Exit polls showed Likud, allied with the ultranationalist Yisrael Beitenu party, emerging from Tuesday's vote as still the biggest bloc in the 120-member parliament, with 31 seats, despite a drop in their support and a surprise surge by a new centrist party.

Netanyahu said he intended to form as broad a governing coalition as possible, suggesting he would go beyond a traditional alliance with other right-wing and religious partners.

"The first challenge was and remains preventing Iran from obtaining nuclear weapons," he said in his speech.

Netanyahu has called Tehran's nuclear programme an existential threat to Israel and has stoked international concern by hinted strongly at possible Israeli military action to stop Iran from developing an atomic bomb.

He has said that by the summer, Iran may reach a level of uranium enrichment that would enable it to move rapidly towards building a nuclear weapon.

Iran, which has been hit by Western sanctions over its nuclear activities, says it is enriching uranium for peaceful purposes only.

(Writing by Jeffrey Heller, Editing by Ari Rabinovitch)