Mr Normal's private life in the spotlight

A feud involving the French president's live-in girlfriend, his former partner and his eldest son may have tarnished the new leader's carefully cultivated image as "Monsieur Normale" – credited with helping him defeat his flashy predecessor, Nicolas Sarkozy.

François Hollande agreed to take a question about the family feud during a TV interview yesterday – a sign that in the Twitter era, even French leaders cannot keep their private lives private.

But he certainly tried. Midway through the Bastille Day interview, the reporters asked for his reaction to "tweetgate", as the feud has been dubbed.

The tweet in question was sent out by his companion, Valerie Trierweiler, during last month's legislative election and expressed support for the political opponent of Mr Hollande's ex-partner Ségolène Royal, the mother of his four children. Ms Royal was later defeated in her bid for the parliamentary seat.

Mr Hollande may have agreed to take the question, but he quickly shut it down, saying that he intended to keep his public and private lives separate. He added that he had asked those close to him to do the same.

It may be too late to put the genie back in the bottle, however.

Widely criticised as a vindictive move, the tweet went viral and has dominated news shows.

Mr Hollande and his children were said to be furious, but all sides moved into damage-limitation mode and kept the feud under wraps. Ms Trierweiler has since kept a low profile and was notably absent when Mr Hollande visited the Queen last week in London.

The Twitter account of Mr Hollande's eldest son, Thomas, 27, reads discreetly: "I don't count on tweeting for the moment." But his silence was broken last week when he spoke out against Ms Trierweiler's actions to Le Point. "I knew that something could come from [Valerie] one day, but not such a big knock. It's mind-blowing," he was quoted as saying. "It upset me for my father. He really hates it when his private life is spoken about."

Then he added what many were already thinking: "It destroyed the 'normal' image that he'd built up."

The Élysée tried to defuse the comments, saying on Friday that they were made during a "personal interview". Thomas Hollande has said some comments were taken out of context. But the remarks have reignited the "tweetgate" debate and are thought to have pushed his father into speaking out.

Since the Le Point article, Ms Trierweiler has been spotted by Mr Hollande's side in a clear show of unity. The French media reported that Mr Hollande allowed diners to take photographs during an intimate dinner with her at a swish Paris restaurant last week. Ms Trierweiler is also to accompany him on engagements this weekend. Yesterday, she had a front-row grandstand seat for the Bastille Day military parade.

"This is really serious for him now. That's why he's going on TV," said a political communications expert, Arnaud Mercier. Mr Hollande answered the reporters' questions in Saturday's interview with his trademark good nature, but it was clear he didn't want to dwell on the topic.

The colourful amorous exploits of French leaders is nothing new.

For instance, François Mitterrand, president from 1981 to 1995, had a secret daughter with a mistress. But the French press, who have made it a point of honour to be protective of politicians' private lives, kept Mitterrand's exploits out of the papers.

In today's world, however, a politician's every public move is under the scrutiny of smartphones and Twitter, and maintaining their privacy is harder than ever – even in France.