Former Frankfurt and Hoffenheim player Preuss, 26, joined from Sunderland and played 17 games last term.

Kitching, 21, also moved to Liverpool last year, having previously been at Sheffield United, Chelsea and Watford.

"It's great news for the club and for me. I enjoy working with both keepers," goalkeeping coach Craig Dootson said.

"I think going forward it's the continuity of keeping two keepers who are comfortable in each other's company and who are competitive."