* Irish c.bank says expects EU/IMF loan, minister cautious
* IMF-Europe mission starts in Dublin
* Mkts rebound, Spanish bonds sell at modestly higher yields
* Unicredit CEO says has "nightmares" about euro zone crisis
* Trichet warns of "dependency" on ECB emergency measures
(Adds Lenihan on contingency capital, Trichet on dependency)
By Lorraine Turner and Carmel Crimmins
DUBLIN, Nov 18 (Reuters) - Ireland's central bank chief said on Thursday he expected Dublin to receive tens of billions of euros in loans from European partners and the IMF to provide contingency capital for its shattered banks.
Central Bank Governor Patrick Honohan was speaking as a joint mission of the European Commission, the European Central Bank and the International Monetary Fund began talks at the bank and the finance ministry on a possible rescue package.
"The intention is and the expectation is, on their part and personally on my part, that negotiations or discussions will be effective and a loan will be made available and drawn down as necessary," Honohan told state broadcaster RTE.
"We're talking about a very substantial loan for sure -- tens of billions, yes," Honohan said, acknowledging substantial outflows of funds from the Irish banking sector since April.
The government said the talks would "undoubtedly" run into next week before a decision is taken on whether to make a formal application for assistance.
Finance Minister Brian Lenihan told parliament the government was not yet at the point of requesting a loan and he could not put a figure on the amount needed. But what was under discussion was "substantial contingency capital to be made available to back Ireland".
He insisted the IMF and EU would not have any input into Ireland's budgetary measures, even though EU rules stipulate that any emergency lending can only be granted to a government that signs a strict fiscal conditionality agreement.
In a move to calm savers, Lenihan said the government was extending an unlimited guarantee for depositors until the end of next year, six months longer than previously announced.
Opposition finance spokesman Michael Noonan told parliament: "I have had ... constituents ringing me to know whether they should open sterling accounts and move their money out."
Irish banks have suffered withdrawals from corporate clients and Honohan said that had necessitated exceptional funding from the Irish central bank on top of ECB liquidity assistance.
After 10 days of losses, European stock and bond markets and the euro rebounded on expectations Ireland would become the second euro zone country after Greece to receive a bailout to cope with high debts and deficits.
Dublin's borrowing costs have gone through the roof since late October as concerns about the banks' swelling liabilities and German-driven EU moves to create a system for restructuring stricken euro zone states' debts unsettled investors.
Irish bond spreads over German Bunds narrowed and the cost of insuring Irish, Portuguese and Greek debt against default fell as markets anticipated a likely rescue.
Spain found solid demand for 3.6 billion euros in 10- and 30-year bonds at an auction but had to pay a higher price than two months ago, as did fellow euro zone struggler Portugal, which sold treasury bills on Wednesday.
That helped dampen fears of contagion from Ireland to other highly-indebted euro zone members.
NIGHTMARES
The chief executive of Italy's biggest bank, Federico Ghizzoni of UniCredit, said he had "nightmares" over the euro zone debt crisis and was worried about Europe's ability to address sovereign debt issues urgently.
"I am concerned about the fact that if not politically properly addressed, it will continue to be in the market, generating volatility," Ghizzoni told reporters in Frankfurt in a rare public airing of fears shared by many senior bankers.
European Central Bank President Jean-Claude Trichet voiced concern at the risk of bank dependency developing on the ECB's emergency liquidity measures as conditions normalise.
Irish banks, largely shut out of interbank lending due to concerns about their solvency, are almost entirely dependent on ECB funding, which reached 130 billion euros by end-October, plus an extra 35 billion euros from the Irish central bank.
EU sources have told Reuters Ireland may need assistance of between 45 billion and 90 billion euros, depending on whether it needs help only for its banks or for public debt as well.
In an indication of potentially tough negotiations ahead, France said Ireland may have to raise its ultra-low 12.5 percent corporation tax rate -- a taboo in Irish politics -- in return for the assistance package.
Higher-tax countries, including Britain, Germany and France, whose approval would be required for any emergency loans, have long seen the Irish rate as a form of unfair competition.
But Irish Deputy Prime Minister Mary Coughlan told parliament the government would not raise the corporate tax rate. "It's non-negotiable," she said.
Prime Minister Brian Cowen has repeatedly rejected suggestions that his government is discussing a bailout that would place public finances under EU-IMF supervision.
Lenihan is due to detail a four-year, 15 billion euros budget-cutting plan next week and the government will put a 2011 austerity budget to parliament on Dec. 7.
Some analysts said Cowen is playing for time to avoid applying for aid before a key Nov. 25 by-election that could reduce his parliamentary majority to just two seats.
Euro zone sources said there was an agreement in principle to trigger aid when the joint mission completes its work -- perhaps in days -- and the aid would not be just for the banks.
Ireland has said the bill for cleaning up its banks could top 50 billion euros but investors fear the final figure could be even higher given rising residential mortgage arrears, deposit outflows and higher funding costs.
Britain, whose banks have around $150 billion of exposure to Irish debt, has said it stands ready to help. Prime Minister David Cameron told parliament London could provide bilateral assistance or join an EU mechanism, or both. (Additional reporting by Natsuko Waki in Dublin, William James in London, Arno Schuetze and Edward Taylor in Frankfurt; Nick Vinocur in Paris, writing by Paul Taylor, editing by Mike Peacock)