PARIS (Reuters) - From bank runs to credit crunches, regulators and investors are asking French banks about their preparations for any market ructions that might be caused by Marine Le Pen faring better than expected in the presidential election, banking sources said.

Marine Le Pen, French National Front (FN) political party leader and candidate for French 2017 presidential election, attends a political rally in Bordeaux, France, April 2, 2017. REUTERS/Regis Duvignau

Far-right leader Le Pen has said that if she becomes president she would call a referendum on ditching the euro, dubbed “Frexit”, finance state spending through central bank money-printing, force commercial banks to lend small firms and halve the maximum rates that banks can charge clients.

Opinion polls indicate she has a good chance of coming out on top of the first round of voting on April 23, with her share of the vote projected at 25-30 percent. But they see her losing to centrist Emmanuel Macron in a May 7 runoff.

Regulators and investors are unwilling to rule out any surprises following the Brexit and U.S. presidential votes last year which confounded pollsters’ expectations.

After French bond yields spiked in February on poll gains by Le Pen, ECB supervisors have sought to ensure banks have fully sized up the risks of the unexpected, four senior bankers told Reuters, speaking on condition of anonymity due to the political sensitivity of the matter.

“We’ve been asked what’s our plans for different scenarios including Frexit,” one of the bankers said.

The ECB declined to comment.

One scenario lenders have been asked about is the possibility of Le Pen scoring higher than predicted in the first round, thus increasing her chances of winning the presidency in the runoff two weeks later.

“For a fortnight we’d be absolutely fine to get through any difficulties,” said a second banking executive, speaking about a possible short-term liquidity squeeze in credit markets. The industry could easily weather a bout of brief volatility, the banker added.

Banks are taking the requests in their stride since ECB officials are including the questions in their regular surveillance checks, rather than asking them to separately compile and submit detailed plans.

The lenders are also having to outline their preparations to foreign investors, according to the sources. In some cases they have had to explain how the election process works, with the first round serving to whittle down a wide field of candidates to just two hopefuls, who will contest the runoff.

“Foreign investors are asking a lot of questions. We have to keep explaining that there are two rounds,” said a third senior executive at French bank.

Some Paris-based lawyers said they were getting questions from investors about whether it was legally possible for France to dump the euro, how the Frexit process might work and what the state could do if a bank run resulted.

“What’s sure is that if there is a risk of a bank run and something needs to be done, the state can do it by decree,” one lawyer said, citing the example of Cyprus implementing capital controls when its banks faced collapse in 2013.

Meanwhile, retail French investors are keeping their money liquid with popular tax-free regulated savings accounts seeing large inflows in the last three months, said Pierre-Rene Lemas the head of the state-backed Caisse des Depots, which collects the money deposited in such accounts at banks.