The Israeli prime minister, Binyamin Netanyahu, has voiced support for Kurdish statehood, taking a position that appears to clash with the US preference to keep sectarian war-torn Iraq united.

Pointing to the mayhem in Iraq, Netanyahu on Sunday called for the establishment of an independent Kurdistan as part of a broader alliance with moderate forces across the region, adding that Israel would have to maintain a long-term military presence in the West Bank even after any future peace agreement with the Palestinians.

Netanyahu laid out his positions in a policy speech that marked his most detailed response to the gains made by Sunni extremists fighting in Iraq. His endorsement of Kurdish independence, as well as his tough position on the West Bank, put him at odds with prevailing international opinion.

In a speech to a Tel Aviv thinktank, Netanyahu said that the rise of both al-Qaida-backed Sunni extremists, as well as Iranian-backed Shia forces, had created the opportunity for "enhanced regional cooperation". He said Jordan, which is facing a growing threat of spillover from conflict in neighboring Iraq and Syria, and the Kurds, who control an oil-rich autonomous region of northern Iraq, should be bolstered. "We should ... support the Kurdish aspiration for independence," Netanyahu told the thinktank, going on to call the Kurds "a nation of fighters [who] have proved political commitment and are worthy of independence".

Israel has maintained discreet military, intelligence and business ties with the Kurds since the 1960s, seeing in the minority ethnic group a buffer against shared Arab adversaries. The Kurds have seized on recent sectarian chaos in Iraq to expand their autonomous northern territory to include Kirkuk, which sits on vast oil deposits that could make the independent state many dream of economically viable. The Kurds have long held aspirations for independence, but have said seeking nationhood is not realistic at the current time. The international community, including neighboring Turkey as well as the US and other western countries, are opposed to the breakup of Iraq.

Since the outbreak of hostilities in Iraq, Washington has been insistent that it the crumbling unity in the country restored. Last Tuesday, the US secretary of state, John Kerry, visited Iraqi Kurdish leaders and urged them to seek political integration with Baghdad.

Netanyahu's call for a long-term military presence in the West Bank also risked triggering international criticism. The Palestinians seek all of the West Bank, captured by Israel in the 1967 Six-Day war, as the heartland of a future independent state, a position that is largely endorsed by the international community. The territory is flanked by Israel on the west and Jordan on the east.

Netanyahu said that given the threats in the region, Israel would have to maintain a military presence throughout the West Bank for the foreseeable future. "We must be able to stop the terrorism and fundamentalism that can reach us from the east at the Jordan line and not in the suburbs of Tel Aviv. He went on to say that whoever does not accept Israel's need for a security presence "isn't facing reality".

While conceding that there might someday be a peace agreement creating an independent Palestinian state, he argued that Israel could not turn over its security needs to either the Palestinians or international forces. He said Palestinian forces are "not capable" of ensuring security, and foreign forces would eventually withdraw. "Therefore we must understand that in any future agreement with the Palestinians, Israel will have to continue controlling security in the territory up to Jordan for a very long time," he said.