OTTAWA -- Facebook and Microsoft have signed onto a declaration promising a dozen initiatives to protect the integrity of the Canadian election this fall -- including removing phoney social-media accounts and fake content.

But other tech giants like Google and Twitter have not signed on.

The "Canada Declaration on Electoral Integrity" is being announced today by Democratic Institutions Minister Karina Gould, just hours before an international committee of politicians is to begin a three-day meeting in Ottawa aimed at figuring out how best to protect citizens' privacy and democratic fairness in the age of social media.

Committee members will also grill representatives from a host of internet giants -- Facebook, Google, Twitter, Microsoft, Amazon and Mozilla -- on what they're doing, or not doing, to prevent abuse.

Politicians from all three major parties in Canada have come to the conclusion that government needs to regulate the tech giants because they can't be relied upon to regulate themselves.

However, by signing onto Gould's declaration, Facebook and Microsoft are signalling their willingness to voluntarily tackle some of the problems that politicians fear threaten democracies around the globe.