But the newshounds' slavering turned progressively to silence under the lofty ceiling and classical furnishings of the Elysee's banqueting hall as the President arrived, dressed in a dark-blue suit and matching tie, via a red-carpet walkup. A large tricolore and a European flag added to the towering, conservative, institutional message.
For 2 hours, Hollande, 59, spoke with the hauteur of a de Gaulle as he brushed aside questions about the affair. And he resorted to the dry, technocratic lexicon of a Valery Giscard d'Estaing, another conservative forerunner, when he explained, for more than 30 minutes, an economic shift from Socialist idealism to Social Democratic pragmatism.
"Everyone in their personal lives can go through tough times," Hollande said, looking rigid and rehearsed as questions about the affair kept coming up. "That is the case for us, they are painful moments. But I have one principle: these private affairs are dealt with in private. This is neither the time nor the place to do it so I will not be responding to any questions about my private life."
The French media traditionally do not intrude into the president's personal life, but the affair leaped into the public domain once it become clear that there were implications for the position of Trierweiler, who has five taxpayer-funded staff.
Trierweiler, 48, a journalist for the glossy photonews magazine Paris-Match, put her career on hold in 2012 to be France's "premiere dame", a role that combines charity work with appearances in haute couture.
She has been Hollande's girlfriend for seven years. Hollande had an affair with her while living with his former partner, Segolene Royal, another Socialist Party heavyweight who is the mother of his four children.
Pressed to answer, Hollande said Trierweiler's official status would be resolved in time for an official visit to the United States starting on February 11.
The couple are due to spend a night at the White House as guests of Barack and Michelle Obama.
For the rest of the event, Hollande stuck stiffly to his message of economic change. Describing himself as "a Social Democrat" - last year he voiced admiration for the pro-business reforms of former German Chancellor Gerhard Schroeder - he fleshed out plans for a so-called responsibility pact with the private sector to help ease France's unemployment crisis.
Under it, by 2017 businesses will be freed from a payroll tax costing 30 billion ($49 billion) annually that contributes towards family allowances. Acknowledging that public spending was too high, he also unveiled plans to reduce the state's budget by 50 billion, again by 2017, with the cuts overseen by a "strategic committee" which would meet every month.
Left-wing trade unions and politicians predictably voiced hostility to the scheme, but the big employers' federation and the main association of small businesses and self-employed gave it a cautious welcome. The financial daily Les Echos warned that in real terms, Hollande's reforms might be somewhat less than meets the eye. Out of the 30 billion that businesses will save in payroll taxes, 20 billion is already accounted for under a fiscal change enacted last year, and the cuts in public spending amount to only 4 per cent over three years.
Analysts said the change in tone, if not substance, was striking and predicted the outcome - provided the affair recedes - would determine the fate of Hollande's presidency.
Hollande already has the lowest opinion ratings of any president in recent French history, but this is closely connected with France's sick economy and his reputation for flip-flopping when lobbied by interest groups.
Weekend opinion polls found that three out every four questioned said they were indifferent to the revelations about the affair and that some respondents even felt slightly more positively towards Hollande as a result of it.
"He can't turn back now," said Jerome Fourquet from opinion pollsters Ifop. "The big question is how, in concrete terms, the reforms will be carried out."
France's first lady
* Entitled to an unofficial private office at the Elysee.
* A bodyguard and access to presidential drivers.
* Five taxpayer-funded staff costing 19,742 ($32,200) a month.
* Eight people worked in the office of Carla Bruni-Sarkozy for a total of 36,448 a month.
- Independent