TEHRAN Hamas' top political leader thanked Iran, his militant movement's most powerful ally, for its support during Israel's punishing offensive in the Gaza Strip, calling the Persian nation on Monday a 'partner in victory' over the Israelis, AP reported.

Khaled Mashaal's visit to Tehran underlined his group's close ties with Iran. But the country's financial backing for the Palestinian militant group could be strained in the coming months, as the Islamic Republic is increasingly struggling with growing financial troubles of its own, worsened by the drop in oil prices.

Mashaal's visit was his first since Israel launched its 22-day assault in late December, aimed at stopping Hamas rocket fire into southern Israel. The fighting killed nearly 1,300 Palestinians dead, Gaza officials say, along with 13 Israelis.

A fragile cease-fire went into effect two weeks ago but has since been tested by sporadic Palestinian shelling and retaliatory Israeli airstrikes. Hamas has claimed victory simply by surviving the onslaught.

Israel and the United States accuse Iran of supplying Hamas with weapons, including rockets. Tehran denies the charge, saying it supports Hamas financially - believed to be to the tune of hundreds of millions of dollars. The funding has been vital for sustaining Hamas under the crippling blockade that Israel and Egypt have imposed on Gaza since Hamas took it over by force in 2007.

Mashaal, who lives in self-imposed exile in Syria, said Tehran played a 'big role' in helping Hamas during Israel's assault with money and moral support.

'God made us victorious in Gaza, and we, the Hamas movement, came to say thank you to Iran, which stood with us,' Mashaal said Monday during a speech at Tehran University.

'You are our partners in the victory in Gaza,' he said, addressing the Iranian people, then specifically thanked President Mahmoud Ahmadinejad and supreme leader Ayatollah Ali Khamenei whom he met separately on Sunday. 'Thank you for all the financial, political and popular support which you have given to us. The Palestinian people will not forget.'

Israel, along with the U.S. and Europe, considers Hamas a terrorist group. But Iran sees Hamas as justifiable resistance to Israel and the rightful Palestinian government, since 2006 elections that Hamas won.

Iran and Hamas are ideologically different - Iran espouses a fundamentalist Shiite version of Islam, while Hamas adheres to an equally strict rival Sunni version - but the Palestinian militant group gives Tehran a key foothold on the doorstep of Israel and Arab allies of the United States.

Tehran has never revealed the amount it provides to Hamas, but the group has said it received hundreds of million dollars from Iran over the past year.

That's only a fraction of the billions Iran earns from oil exports, the main source of the country's foreign income. But the tumble in oil prices - from a record $147 in July to around $40 a barrel - has gouged Iran's revenues at a time of belt-tightening at home. The government plans to cut many subsidies to fight a budget deficit of billions of dollars - which could fuel social disenchantment, already high over a domestic inflation of about 25 percent.

'Iran's generosity could falter when its annual $100 billion oil income falls to $35 billion due to falling oil prices,' Saeed Laylaz, a prominent Iranian political analyst, said.

But he said Iran was unlikely to cut off the flow of cash completely, since Hamas and Lebanon's Shiite Hezbollah group - another close ally of Tehran - 'are important for Iran's foreign policy toward the U.S.'

Iran's presidential elections in June and persistent international pressure over its disputed nuclear program could also force Tehran to turn more to home matters.

Separate from the government funding to Hamas, Iranians regularly donate money for the Palestinians to the Red Crescent or to charities - some of which may go through Hamas to Gazans. That money too could be hit by economic woes.

At a fundraiser Monday for Palestinian children orphaned during the offensive, housewife Mehraneh Abdi, 43, gave $20. She said she wanted to give more but can't 'since the cost of living has increased sharply in the past months in Iran.'

Down the street, teacher Minoo Rasai said the government shouldn't be giving so much either, noting that she hasn't received part of her salary for months. 'The government should pay our salary rather than paying people abroad,' she sighed.