Minka Kelly steps out and takes to Twitter to deny romance rumours with Sean Penn after he joined her for recent birthday dinner

Minka Kelly made it clear on Wednesday that she was not dating Sean Penn and seemed entirely happy with that situation.

The 35-year-old actress gave a small smile as she left the Rise Movement gym in Los Angeles after a workout that morning.

On the same day, Minka wrote on Twitter that rumours of her dating the 54-year-old Oscar winner were not at all true.

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Pleased: Minka Kelly looked cool and happy after exercising in Los Angeles on Wednesday - she denied a relationship with Sean Penn on the same morning

Pleased: Minka Kelly looked cool and happy after exercising in Los Angeles on Wednesday - she denied a relationship with Sean Penn on the same morning

'Not my nature to address gossip but hoping this last one goes away already. Not dating a friend I had a group dinner with. #Sillymedia,' she wrote, alluding vaguely to the rumours about her and Sean. 

Her brown hair pulled into a messy ponytail, the Friday Night Lights actress was simple but stylish for her post-workout look.

Dark shades covered most of Minka's face, while a tan shoulder bag hung at one side. 

Simple style: Her hair in a ponytail, Minka kept things simple in a tank top, leggings, and flip-flops
Simple style: Her hair in a ponytail, Minka kept things simple in a tank top, leggings, and flip-flops

Simple style: Her hair in a ponytail, Minka kept things simple in a tank top, leggings, and flip-flops

Nothing to hide: With an open expression - even a smile - Minka made it clear she was hiding nothing

Nothing to hide: With an open expression - even a smile - Minka made it clear she was hiding nothing

She had a double-layered top, with a white sports bra visible underneath a black tank top that showed off the actress' slim figure. 

Black-and-white leggings and flip-flops finished off Minka's look for the day.

Other than exercise, the most notable part of the morning for Minka was seen on social media.

Clarification: Minka took to Twitter on Wednesday to clarify that she has not been dating Sean Penn

Clarification: Minka took to Twitter on Wednesday to clarify that she has not been dating Sean Penn

Rumours: Since sharing a dinner in June, rumours have circulated about the actors dating in secret

Rumours: Since sharing a dinner in June, rumours have circulated about the actors dating in secret

The rumour will went into overdrive when Minka celebrated her birthday with a group of friends in California's Napa Valley on June 24.

Among the four guests was Sean, who reportedly told the others that he and Minka had first met at a charity event supporting Haiti.

Photos quickly circulated, fuelling rumours of a romance - single Sean had broken up with his long-time girlfriend, Charlize Theron, only weeks earlier.

Intimate gathering: For her birthday, Minka was  joined by a handful of pals at a posh restaurant in Napa Valley

Intimate gathering: For her birthday, Minka was joined by a handful of pals at a posh restaurant in Napa Valley

Guest of honour: Sean's unexpected presence at the birthday made it look like the two might be dating - they met at a Haiti fundraiser

Guest of honour: Sean's unexpected presence at the birthday made it look like the two might be dating - they met at a Haiti fundraiser

Minka has rarely commented on her dating life, despite having gone out with high-profile men like baseball player Derek Jeter and Captain America star Chris Evans.

Sean, meanwhile, is well-known for his relationships with famous women like ex-wives Madonna and Robin Wright.

He has two adult children from his two-decade marriage to Robin, which ended in divorce in 2010.

Single man: He broke up with long-time girlfriend Charlize Theron (right on May 16) recently, the latest of several high-profile women in a relationship with Sean

Single man: He broke up with long-time girlfriend Charlize Theron (right on May 16) recently, the latest of several high-profile women in a relationship with Sean

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