Gerard Houllier will not officially take charge of Aston Villa until after Monday's Barclays Premier League clash at Stoke.
The former Liverpool boss shook hands with Villa owner Randy Lerner on a three-year contract with the midlands club, but Press Association Sport understands that Houllier still has to tie up some loose ends with the French Football Federation after resigning as technical director before he can formally replace Martin O'Neill.
Houllier was still due to hold a press conference on Friday, while caretaker boss Kevin MacDonald will be in charge for a sixth successive game against Tony Pulis' side.
Houllier is now expected to be in the Villa dugout for the first time for the home clash with Bolton on September 18.
The Frenchman plans to hold talks with MacDonald at Villa's Bodymoor Heath training complex to discuss his role in the new set-up. Former Liverpool midfielder MacDonald is currently reserve team coach.
Houllier revealed he rejected other offers before taking charge at Villa and hopes to build on the success achieved under O'Neill.
He said: "It was really starting to tickle me. I wanted to go back pitchside. I had, of course, other proposals but this one seemed to be the most interesting in terms of working conditions and environment.
"Aston Villa is not a club on the same level as Liverpool, let's be objective and honest. It's a club that according to me has belonged between seventh and 12th place in the Premier League.
"But, above all, it's a historic club which has won the European Cup. It's a club which has got good infrastructure and a fine team which is after one thing - to improve year on year."