(Adds details on deals, acquisitions, shares)
MADRID, July 29 (Reuters) - Spanish toll road operator Abertis said on Wednesday it had used part of the cash obtained from the listing of its telecoms arm Cellnex to write down assets and was now getting ready for new deals and acquisitions.
It said it was studying the acquisition of 8 motorways in Spain, Italy, Chile, Brasil, the United States and Puerto Rico for a total value of up to 9 billion euros ($9.93 billion).
The firm, which booked 2.7 billion euros ($2.98 billion) from the listing, passed a 769 million euros provision on its domestic AP-7 motorway asset after the government challenged a 2006 agreement to compensate Abertis for falling traffic.
Having reduced debt, it said it now would boost treasury stock by using 963 million euros to buy up to 6.5 percent of its own shares at 15.70 euros each, adding it was ready to use it in potential corporate deals.
Shares in Abertis were flat at 0800 GMT, with analysts saying the buy-back announcement offset the write-down while a steady traffic improvement made up for the a slight miss on the first-half core profit.
"These are busy results but we see the fundamentals continuing to improve while the negative sentiment around the AP-7 guarantee now has a line in the sand drawn," said RBC Capital markets analyst Andy Jones in a note to clients.
The Barcelona-based company posted a 5 percent rise in comparable core profit to 1.36 billion euros in the first six months of 2015, helped by rising traffic on its Spanish, French and Chilean motorways, although it missed a 1.47 billion euro analysts' forecast.
Net profit came in at 1.68 billion euros from 308 million euros in the same period last year. Excluding one-off effects, it was up 5 percent year-on-year. ($1 = 0.9060 euros) (Reporting by Julien Toyer Editing by Jeremy Gaunt)