The 25-year-old, who can play at fly-half or centre, replaced foot injury victim Byrne in the number 15 jersey during last season's autumn internationals to further enhance his versatility in the Wales back-line.
The Titans now boast six internationals for their debut season, including Great Britain winger Brian Carney, who started training with the Titans on Monday.
Liverpool, however, are now expected to follow up their initial interest with a firm offer to link Ziege with two fellow German internationals at Anfield next season.
We took a hit at the start of the season not playing some of the internationals because of training reasons and we took a hit losing to the Dragons at home.
Alongside their coverage of the FA Cup, ITV will continue to broadcast all England home qualifying matches through until the end of the 2011-12 season as well as home and away friendly internationals (home friendlies were previously held by Setanta).
Last season their star-studded squad - that now contains 16 internationals from nine nations - made the semi-finals of the French league and lost to Cardiff Blues in a thrilling Amlin Challenge Cup final.
Kennedy, who impressed in his debut against the Pacific Islanders and again against the All Blacks in the autumn internationals, was out of contract at Irish at the end of the season.