MADRID (Reuters) - Spain's stock market regulator said on Wednesday it had asked interested parties involved in the taking over of Abertis to not reveal private information about the 18-billion-euro deal.

"We are closely following all the information and leaks about the takeovers and we have acted this morning to suspend trading until there is sufficient public information," a spokesman for the CNMV regulator said.

Spain's ACS and Italy's Atlantia agreed terms on Wednesday to jointly take over Abertis, ending a potential bidding war for the Spanish highway concessions group.

The CNMV suspended trading in Abertis and ACS before the market opened on Wednesday.

(Reporting by Andres Gonzalez; Writing by Angus Berwick; Editing by Paul Day; Editing by Paul Day)