Both outfits spend a fortune bribing lobbying US politicians to get their way, but they decided not to use their political pawns to harm the other during the truce.

However, with regulators around the world threatening to impose limits on the power of the biggest technology companies, the two rivals -- which compete in web search, cloud computing and artificial intelligence -- are now free to step up behind-the-scenes lobbying efforts and public complaints against one another.

The old non-aggression pact, forged at the time by two new CEOs wanting a fresh start on a formerly acrimonious relationship, had already been fraying before it lapsed in April. Then, the companies feuded publicly over a proposal to force Google to pay news publishers for content and squabbled more quietly over technology for selling search ads.

Neither company is eager to extend or renew the alliance, according to sources in both companies.