Actress Hayden Panettiere and boxer Wladimir Klitschko are reportedly engaged, but the news is still a secret.

The Nashville star and the Ukrainian heavyweight did not publicly confirm their relationship nor engagement despite being photograpphed kissing.

"Very people know, and she isn't wearing her ring publicily yet," a source said. US Weekly reported that the couple may plan for a wedding this summer.

Panettiere, 23, told TMZ in January that she and her fiance, who is the younger brother of the World Boxing Council heavyweight champion Vitali Klitschko, were "just good buddies."

Klitschko, who is 14 years older than the actress is the fifth longest reigning Heavyweight Champion of all time. Not only is he a world-known boxer, he also has some acting credentials under his belt. He previously had a role in Ocean's Eleven and also starred in Chris Cornell's music video, Part of Me that debuted back in 2008.

According to a report, last March 2012, Klitschko auctioned off his 1996 Olympic gold medal for a million dollars in which he donated all of the funds towards Ukrainian children in need. The medal was later returned to him.

Klitschko is way taller than Panettiere. He measures at 6-foot-6, and towers over the 5-foot-2 television actress.

The couple once dated for two years and called it quits in 2011, and claimed the break-up happened because of struggles of long-distance relationships. The two have refused to open up about their recent romance, according to reports.

Panettiere has previously been said to have dated Heroes costar Milo Ventimiglia. She was linked to One Tree Hil star Stephen Colletti. Just recently, the actress and former New York Jets player Scotty McKnight fueled a romance, but broke up in December after dating for about a year and a half.

The actress revealed to US Weekly that she preferred dating athletes.

"They're in similar circles, where they understand the schedule, the work ethic, the social aspect," Panetierre explained, "but they're not exactly in your industry, so it works out well."