* Bank chiefs - two years not enough time to prepare
* Banks face 'enormous task' in setting up EU subsidiaries
* EU's Juncker warns no market access 'a la carte' (Recasts, adds EU taskforce)
By Huw Jones and Lawrence White
LONDON, Sept 14 (Reuters) - Top City of London executivessaid banks will need more than two years to adapt to Britain'sdeparture from the European Union if the market is to avoiddisruption, while the EU's top official called for a promptstart to divorce talks.
Once Britain begins formal negotiations for exiting the EU,known as Article 50, it will have two years until it ceases tobe a member of the bloc.
On Wednesday, three of the most senior executives in theCity told lawmakers this was not long enough for banks to adaptand they would need more time before a trade deal is put inplace.
"It's a multi-year process if it's going to be completedsafely and not going to risk financial stability," AlexWilmot-Sitwell, president of Bank of America Merrill Lynch inEurope told a House of Lords committee. "I suspect it'stwo to three years."
HSBC Group Chairman Douglas Flint and AllianzGlobal Investors Vice Chair Elizabeth Corley also warned of thedangers posed by hasty change.
Seeking leeway from Brussels could be difficult, not leastbecause there is disagreement in the British government aboutwhat concessions to make in negotiations.
The talks cannot start until Prime Minister Theresa Mayformally sets the two-year countdown to British departure.
In Strasbourg, Jean-Claude Juncker, who heads the EU'sexecutive European Commission, urged that to be done quickly andrepeated the EU negotiating position that Britain could notretain its full EU market access if it blocks free immigrationfrom the EU.
"There can be no a la carte access to the single market,"the Commission president told the European Parliament in hisannual State of the Union address.
"Only those can have unlimited access to the internal marketwho accept that there will be free access for persons andgoods."
Banks in Britain depend on an EU "passport" to serve clientsacross the 28-country bloc from one base and lenders worry thatthese passporting rights will end after Britain leaves the EU.
The European Commission has named a senior German tradenegotiator to join France's former EU finance commissioner,Michel Barnier, at the head of the team negotiating Britain'sdeparture from the European Union.
In parliament on Wednesday, May said that the government isworking for "the right deal" on trade relations with the EU,without giving further details.
NO 'LEGO SET'
Banks are making contingency plans to move some of theiroperations to continental Europe if Britain does not negotiateaccess to the bloc's single market after Brexit.
Wilmot-Sitwell said the financial sector is not a "Legoset", where you can pull up and move pieces without affectingclients and financial stability. "You don't move nuclear wastein a race," he added.
HSBC's Flint, who is on a panel advising the government onpost-Brexit trading terms, said it would take several years fora bank in London to complete the "enormous task" of setting up anew subsidiary in the EU.
Tinkering with London's financial "eco-system" couldundermine new rules regulators have put in place since the2007-09 financial crisis, Flint said. It could also impactcustomers across Europe, he said.
London accounts for 69 percent, or $928 billion, of theoff-exchange euro-denominated interest rate derivatives marketand President Francois Hollande of France has said clearing ineuro-denominated contracts should be moved to the euro zone.
That would bump up costs by forcing banks and users to havemultiple piles of cash to back trades, Flint said. (Editing by Elaine Hardcastle and Susan Thomas)
HSBC Holdings (HSBA)