There's been lots of talk about the possibility of a Grexit or a Brexit — Greece or Britain leaving the European Union.
But what about France?
In the wake of the Paris terrorist attacks and subsequent appeals for tighter borders, Morgan Stanley International CEO Colm Kelleher told CNBC on Thursday that "it's not inconceivable to talk about Frexit with the rise of the National Front," the far-right party in France.
"Europe is the [Syrian] migration issue, without a doubt. That will test the European Union," he contended.
Kelleher, also president of institutional securities at Morgan Stanley, said on "Squawk Box" that he does not see a French exit from the European Union actually happening. "[But] you have huge strains now on the union because of this."
Marine Le Pen, leader of the National Front, on Monday called for an "immediate halt" to the refugee flow into France.
In a statement, her party pointed to news that one of the attackers may have arrived in Greece last month "among the mass of migrants who flow into Europe each day."
Over the summer, Le Pen called herself "Madame Frexit" in a television interview. But in recent months, she's softened her stance.
The National Front, which has long called for stricter border security and a crackdown on Islamic extremists, has gained in popularity ahead of regional elections next month, perhaps bolstering Le Pen's chances as a presidential candidate in 2017.
French President Francois Hollande, a socialist, has tacked right since the attacks, ordering airstrikes in Syria on militants from the so-called Islamic State, who claimed responsibility for the Paris violence.
On Monday, he vowed to forge a united coalition capable of defeating the jihadists at home and abroad.