This week Mr Sarkozy bagged another Socialist grandee, Jack Lang, who also enjoys wide popularity.

ECONOMIST: France's Socialist Party

If only by 37 votes, Jack Lang, the education minister, lost Blois, which he had controlled since 1989.

ECONOMIST: France

It took a last-minute intervention by the culture minister of the day, Jack Lang, to save Mr. Buren's project, which has since proved immensely popular and was given a much-needed makeover in 2010.

WSJ: Daniel Buren's Bright Periphery | 'Excentrique(s) Travail In Situ' at the Grand Palais in Paris

Despite an effort a year ago to spice up his image, his popularity rating is low (43%, according to Ifop, a pollster), compared with that of Mr Hollande (48%), and way behind those of popular heroes such as Bernard Kouchner (73%) or Jack Lang (67%).

ECONOMIST: Members of the Socialist Party vote for the EU constitution

That same evening, another concert will be held at the United Nations General Assembly in New York, hosted by UNESCO Director-General Irina Bokova and featuring Richard Bona, Dee Dee Bridgewater, Danilo Perez, Derek Trucks and Susan Tedeschi, Jack DeJohnette, Herbie Hancock, Jimmy Heath, Zakir Hussain, Angelique Kidjo, Lang Lang, Romero Lubambo, Shankar Mahadevan, Wynton Marsalis, Hugh Masekela, Christian McBride, Dianne Reeves, Wayne Shorter, Esperanza Spalding, Hiromi and others.

UNESCO: OFFICE IN DHAKA