Surely they're not rowing ALREADY? Simon Cowell and pregnant girlfriend Lauren Silverman are seen having a heated argument

They've been showing their love for one another on a series of PDA-filled excursions over the past few days.

But it seems that Simon Cowell and his pregnant girlfriend Lauren Silverman are starting to tire of one another's company, as they were seen having what appeared to be a heated row in New York on Thursday.

The couple looked to be raising their voices at each other as they had an argument in the back of their car.

Surely you're not rowing already? Simon Cowell and pregnant girlfriend Lauren Silverman were seen having what appeared to be a heated row while in New York on Thursday

Wearing her sunglasses, Lauren, 36, was seen attempting to make a point to Simon, 53, who then raised his hand in a frustrated gesture as he tried to put his side across.

The veins in the music mogul's neck were also see growing ever more prominent as his frustration increased.

The apparent argument is the first time Lauren and Simon have been seen having cross words with each other.

Gestures: Just like on the American Idol judge panel, Simon let his hands do the talking

Getting annoyed: Lauren wore sunglasses but still couldn't hide her frustration at her beau

Irritating: Lauren looked increasingly frustrated by the argument

But while the subject of the row is not known, it was all forgotten as the pair ensured their smiles were fixed firmly in place as they were photographed leaving her Manhattan apartment later in the day.

Dressed in a white T-shirt and jeans, Lauren's baby bump navy blazer could easily be seen from under her navy blazer.

As she grinned brightly, Simon appeared stoic as he walked behind her in a similar white top.

Open-mouthed: Outspoken Simon clearly had a lot to say

Unstoppable: Countless co-hosts have tried and failed to shut Simon up in the past

The X Factor judge carried a brown leather case in one hand, while the other was used to hold a burning cigarette – another Cowell staple – although thankfully nowhere near Lauren.

On Tuesday Cowell raised eyebrows when he chose to light a cigarette as the couple left their Upper East Side apartment.

Puffing away on his cigarette, the X Factor boss looked totally at ease as the pair headed out for a date night at upmarket eatery, Carbone.

All is forgiven: Lauren was soon smiling again as she walked ahead of Simon, who wore a deadpan expression

Playful: Simon flashed the peace sign as he and Lauren left her Manhattan building

And although he was only feet away from the woman who is carrying his first child, Simon didn't seem to have a care in the world as he smoked away to his heart's content.
In spite of his nicotine faux pas, the pair looked utterly loved-up as they enjoyed their romantic day out together in the Big Apple.
Simon and Lauren's easy way around each other has become increasingly apparent as they prepare to welcome their son together.
On Wednesday, Simon was again in a playful mood as Lauren sat on his lap after they had clamboured into a New York cab.

Matching styles: Cowell and Lauren wore similar outfits of jeans and white T-shirt

Ladies first: Ms Silverman walks ahead of Simon Cowell, who brings up the rear as they leave a New York building on Thursday

We're expecting: Simon Cowel will be a first time parent when Lauren Silverman, who is four months pregnant, gives birth

He's got baggage: Cowell was carrying a leather briefcase as he exited a building in Manhattan on Thursday

The pair began their day with a spot of shopping, before enjoying a pampering session at the Tracie Martyn salon.
While it is unclear whether Simon himself had any treatments, Ms Silverman appeared to be glowing after spending the afternoon at the salon of superfacialist Tracie, who counts Madonna, Kate Winslet and Brad Pitt among her celebrity clients.
And she appeared to be so impressed by the treatment that she even stocked up on some skincare products, as she was seen armed with bags from the salon as she headed into her apartment alongside Cowell.

Sparking up: The music mogul enjoys a cigarette... at a safe distance from his pregnant girlfriend

Meanwhile: Cowell's ex Sinitta steps out at London Fashion Week on Thursday evening