The DAX 40 in Frankfurt, meanwhile, continued its impressive upward streak, albeit with difficulty, notching up a tenth consecutive gain (+0.02%, to 25 411.44 points today). Today's rise also allowed it to reach new all-time highs. Over the past ten sessions, the German index has gained 4.64%, including 3.76% since the start of the year.

Today's session was marked by two key events across the Atlantic: the always eagerly awaited U.S. inflation data, and the start of the fourth-quarter earnings season, notably with banking giant JP Morgan.

U.S. Inflation Stabilizes, No Immediate Impact on Monetary Policy

On the macroeconomic front, in December the U.S. Consumer Price Index rose by 0.3%, in line with analysts' forecasts. Year-on-year, it increased by 2.7%, as expected, after a similar 2.7% rise the previous month. Core inflation, which excludes food and energy, rose just 0.2% in December, below expectations of +0.3%, bringing the annual rate to 2.6%, or 0.1 point less than forecast.

This data reveals a stabilization of inflation in the United States, but it is unlikely to be enough for the Federal Reserve to lower its key interest rates. According to CME Group's FedWatch Tool, the probability of a status quo (97.2%) versus a 25-basis-point cut (2.8%) has barely changed. The same tool indicates that a more accommodative monetary policy is only expected at the mid-June meeting.

It is uncertain whether Donald Trump, who has been re-elected as President of the United States and frequently criticizes Fed Chair Jerome Powell, will have the patience to wait that long.

Over the weekend, Powell indicated that he could be targeted by the U.S. Department of Justice over work conducted at the central bank's headquarters. Powell sees this, rightly, as a "pretext" by Donald Trump to exert pressure on the Fed and its chairman. Powell has received support from several of his counterparts. In a joint letter, signed notably by Christine Lagarde, President of the ECB, central bankers expressed their full solidarity with the Federal Reserve System and its chairman, Jerome H. Powell. They added that "the independence of central banks is the cornerstone of price stability, financial and economic stability, in the interest of the citizens we serve."

Start of U.S. Earnings Season

Investors also had to keep an eye on the start of the quarterly earnings season in the United States. JP Morgan (-3.20%, at $314.12) participated in this exercise and fell in New York. The American giant reported earnings above expectations, but lower than the same period a year earlier. Jamie Dimon, Chairman and CEO of the bank, nevertheless remained cautious, stating: "We remain vigilant, and markets seem to underestimate potential dangers—notably complex geopolitical conditions, the risk of persistent inflation, and the high level of asset prices."

Other U.S. financial giants will publish their results in the coming days, including Bank of America, Wells Fargo, and Citigroup on Wednesday, followed by Morgan Stanley, Goldman Sachs, and BlackRock on Thursday.

In France, Vinci and Eiffage were particularly neglected, penalized by the Transport Ministry's decision to levy an additional €2.5 billion from motorway concessionaires to finance infrastructure. Saint-Gobain also ended in the red, hit by disappointing results from Swiss group Sika .