The pair were rumoured to have broken up earlier this month, after starting their relationship in early 2010.
However, a confirmation of the split has yet to arise, with Jenner declaring his love for the singer last week.
A witness has revealed that they were spotted at the Four Seasons Beverly Hills hotel having dinner at the Culina restaurant.
"They had drinks on the patio and moved inside for dinner," the witness told People. "They were kissing and cuddling and were very affectionate. They definitely didn't look broken-up."
On the rumoured break-up, Jenner tweeted last week: "It really upsets me to read all the FALSE!! stories. Avril has always been there for me and is the closest person to my heart. I love her (sic)."
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