The presidential candidate has promised if elected in May to dump the euro and organise a Brexit-style referendum on France's membership in the European Union.
But recently she has appeared to soften her stance, saying a "common currency" could coexist with the national unit.
Addressing a gathering of foreign correspondents, the National Front (FN) leader insisted she had "not changed my mind."
If she won the vote on May 7, she would immediately begin negotiations with the EU on restoring "four fundamental types of sovereignty: territorial, economic, monetary and legislative".
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Six months later she would put the outcome to a "Frexit" in/out referendum.
"Either I will have secured the return of those four sovereignties and I will advise the French to remain in a new Europe of nations, or I will not and then I will advise them to leave the EU," she vowed.
The anti-immigration Le Pen is one of the top contenders for the presidency, buoyed by anger with elites and concern over migration accentuated by a series of jihadist attacks -- factors that fuelled Britain's decision to quit the EU and Donald Trump's rise in the United States.
Most polls show her qualifying for -- but losing -- the run-off second round of the election in May against the conservative candidate Francois Fillon.
But a survey Thursday indicated another candidate, ex-banker and former economy minister Emmanuel Macron, was gaining ground.
The Elabe poll of 995 people conducted on January 3-4 showed the 38-year-old prodigy pipping Le Pen for a run-off spot in two of eight scenarios tested by pollsters.
France's presidential election remains difficult to forecast, with the final line-up of candidates including the Socialist party contender still unknown.