Noriyuki Haga is likely to join Neil Hodgson, Chris Walker and James Toseland in WSB next season after signing a letter of intent to ride Aprilia’s RSV Mille in the 2002 championship.
Haga has been talking to many teams about a return to WSB after a disappointing year in GPs where he struggled to get to terms with the Red Bull Yamaha YZR500 on Michelin tyres.
The Japanese rider is currently in hospital at home recovering from a tooth abcess that caused him to miss the final GP of the year in Brazil.
An Aprilia spokesman said: " We have been in talks with Noriyuki for a long time now and we are very happy to have got the letter of intent signed.
" We should have the rest of the deal done by the end of this week and then we can start planning some testing. "
A final announcement about Haga is expected within the next couple of days and any updates will be posted on www.motorcyclenews.com as soon as the news breaks.