Aretha Franklin issued a statement apologizing for not attending Whitney Houston’s funeral service.

NY Daily News reports:

Aretha Franklin might not have been able to attend pal Whitney Houston’s funeral, but the “Queen of Soul” paid ample tribute to the late superstar just hours later.

In a statement issued Saturday, Franklin, 69, apologized profusely for her absence from the star-studded services, saying that her own poor health forced her to call in sick.

“Regretfully, I am so sorry that I was unable to be with you at Whitney’s service today,” she wrote.

“I had every intention of being there. But unfortunately I had terrible leg spasms and locked leg muscles until 4 a.m. this morning following my concert last night, which I’ve been having for the last few days.”

Just last year, Franklin was hospitalized with an undisclosed illness that had her own fans concerned.

But after resting up during the day, Franklin came back full-force with a solid performance that evening at Radio City Music Hall, during which she paid tribute to the late singer, whom she affectionately referred to by her nickname, “Nippy.”

“She was a very fine young lady” and “one of the best, greatest singers,” Franklin addressed the audience during a piano rendition of Houston’s “I Will Always Love You,” according to KLTV. “She was giving, gave so much of herself.”

“God bless you, Nippy,” she finished off the tribute. “We’ll always remember.”

The night before, Franklin had similarly honored Houston with a moving speech to an audience that included Clive Davis, L.A. Reid and Jesse Jackson.

“She’s moved on up just a little bit higher now. And we don’t wonder where she is,” Franklin said, according to People. “One of the last songs she sung is ‘Jesus Loves Me.’ When God is for you, who can be against you? That’s all that matters.”