SAN FRANCISCO (Reuters) - The United States and the United Kingdom signed a cross-border data access agreement allowing each government to demand information around serious crimes directly from tech companies based in the other country, they announced on Thursday.

The two governments, joined by Australia, also signed an open letter to Facebook asking the company not to proceed with its plan to encrypt its messaging systems without first putting in place safeguards and ensuring court-authorized access for law enforcement.

Reuters reported on the agreements earlier on Thursday.