There will be music from the composer of the Slumdog Millionaire theme, food from an Ethiopian-born Swedish chef and cedar chips sprinkled on the roofs of the portable lavatories. There may also be the faint patter of drizzle on canvas.

The first state dinner of the Obama era, held tonight in a tent village on the South Lawn of the White House, will honour an Indian Prime Minister described by aides as an abstemious vegetarian. At the same time, it will set the tone for formal entertaining by the most glamorous couple to inhabit the White House since the Kennedys.

Michelle Obama has personally supervised the compilation of a guest list 400 names long and the creation of a menu of global cuisine, “possibly including a curry dish”, that will have to avoid seeming too global lest the Obamas’ critics condemn it as a betrayal of apple pie. Invitations to the banquet for Manmohan Singh are the most sought after in town — a town with thousands of powerbrokers but only one superstar.

Hollywood has been enlisted to provide some more: Steven Spielberg, David Geffen and Jeffrey Katzenberg, the billionaire founders of Dreamworks SKG, are all said to be on the list in recognition of their work as “bundlers” of Hollywood donations to the Obama campaign. Mr Spielberg is also the beneficiary of a $550 million (£330 million) investment in his films by Anil Ambani, the Indian tycoon.

Mr Ambani will not be at the White House tonight, according to sources in the Indian delegation, but his older brother, Mukesh, will. He will join a third Indian multimillionaire, Ratan Tata, in a 13-strong group of business leaders whose presence in Washington with Mr Singh underlines the central theme of the first state visit of Mr Obama’s presidency: commerce.

Trade and climate change dominated a rainy day of talks yesterday. Tonight, for a few hours, they will be eclipsed by the first big test of the Obamas’ ability to create something more memorable than mere politics, in what one White House veteran promised would be “the most magnificent tent that you have ever been in”.

The dress code is formal and the identity of Mrs Obama’s designer was being kept secret yesterday, along with the menu. “We still want our guests to be surprised,” her spokeswoman told The Times. “We just want the guests’ experience to be perfect.”

Nearly a year into his Administration, this is Mr Obama’s first formal thank-you to those who helped to put him in the White House. It is the one that counts.

As Dee Dee Myers, President Clinton’s former press secretary, put it: “By the time you get to the eighth state dinner, it’ll be a lot less important.”