Thomas Hollande, French president’s eldest son, has publicly attacked the country’s First Lady Valérie Trierweiler, accusing her of destroying the president’s election-winning “normal image”.

Thomas Hollande says he and his brothers and sisters have made it clear they no longer want to see their father’s partner, Valérie Trierweiler, after she helped destroy their mother Ségolène Royal’s political hopes with a jealous tweet.

Valérie Trierweiler, 47, used Twitter to express her support for the rival of François Hollande’s former partner Ségolène Royal days before France’s legislative elections last month.

Ségolène Royal, 58, went on to lose her parliamentary seat and saw her ambition to become the speaker of France’s Assemblée Nationale vanish with it.

In an interview with the news magazine Le Point, Thomas Hollande, 27, who was active behind the scenes in both his parents’ election campaigns, shatters any attempts by the Elysée Palace to paper over the domestic-turned-political spat.

“What I find reproachful about the tweet is that it put the private life into the public domain,” he told Le Point.

“It pained me on behalf of my father who absolutely detests anyone talking about his private life. It destroyed the normal image that he had constructed.”

Thomas Hollande, French president's eldest son, has publicly attacked the country's First Lady Valérie Trierweiler, accusing her of destroying the president's election-winning "normal image

During a long and bitter election campaign against Nicolas Sarkozy, 57, François Hollande, also 57, had presented himself as Monsieur Normal as a direct contrast to his predecessor’s flashy bling-bling image.

Valérie Trierweiler was portrayed as a more discreet and dignified alternative to the former first lady, supermodel-turned-singer Carla Bruni-Sarkozy, 44.

Thomas Hollande said his father was “stupefied” by the tweet, which was reportedly posted after his father and Valérie Trierweiler fell out over the president issuing an official message of support for Royal, who was standing for parliamentary in the coastal constituency of La Rochelle.

Shortly afterwards Valérie Trierweiler sent a message supporting SégolèneRoyal’s rival, Socialist party dissident Olivier Falorni, who went on to secure a convincing victory.

“I knew that she would do something one day, but not such a huge blow. It’s staggering,” said Thomas Hollande, one of the Hollande-Royal couple’s four children.

He said it was “only logical, no?” that he and his siblings no longer wished to have anything to do with Valérie Trierweiler, a journalist with Paris Match magazine, adding: “What matters is that relations with our father return to normal.”

Thomas Hollande, a lawyer, said he had a tête-à-tête dinner with his father who had asked him not to “add fuel to the fire” over the tweet, which caused a national scandal.

Le Point said the president was likely to refer to the tweet during the traditional 14 July Bastille Day speech, in which he is expected to clarify Valérie Trierwieler’s role.

The president’s son, however, had clearly ignored his father’s advice not to rake over the ashes of the row. Speaking of Valérie Trierweiler, he told Le Point the current situation was causing instability.

“Either she’s a journalist, or she has an office at the Elysée … and, above all, no more tweets,” he said.

He also said his mother had not abandoned her political ambitions, suggesting she could take up a government post.

“A minister? Why not, in a few months? In politics, one is never dead.”

Never far from Hollande’s side during the long election campaign, Valérie Trierweiler’s absence has been conspicuous since the offending tweet. On Monday François Hollande travelled to London to meet David Cameron and the Queen without his partner.

French commentators also pointed out that she had not accompanied the French leader to the G20 summit in Mexico. She is expected to be at François Hollande’s side during the official Bastille Day parade on Saturday on the Champs Elysées.