Weary Zayn Malik cuts a glum figure during NYC trip... as former pal Naughty Boy threatens to leak unfinished track while hinting he deserves credit for Pillowtalk

He is riding high on the stratospheric success of his solo career and his new relationship with Gigi Hadid. 

Yet chart topping singles and a supermodel girlfriend could not help Zayn Malik crack a smile, as he was spied on the streets of NYC looking glum on Thursday. 

The 23-year-old former One Direction star was potentially mulling over the thoughts of former friend and colleague Naughty Boy, who appears to have reignited a feud between the pair. 

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Moody boy: Chart topping singles and a supermodel girlfriend could not help Zayn Malik crack a smile, as he was spied on the streets of NYC looking glum on Thursday

Zayn, who has been frequenting Gigi's home of New York, went for his favoured branch of sporty style in a navy tracksuit comprising of tapered trousers with an anorak top. 

The base of the jacket was a bold red, cascading from a V shape at the top, while he showed off his attention to detail with his navy trousers. 

He showed off his newly sheared head, with a bleached look over the top, while his smattering of designer facial hair was firmly in place. 

Hitmaker: The 23-year-old former One Direction star was potentially mulling over the thoughts of former friend and colleague Naughty Boy, who appears to have reignited a feud between the pair

Glum: Zayn, who has been frequenting Gigi's home of New York, went for his favoured branch of sporty style in a navy tracksuit comprising of tapered trousers with an anorak top

Former friends: Zayn's trip out comes after his former friend and producer Naughty Boy, real name Shahid Kahn, attempted to reignite their feud which has rumbled on since last year

Zayn's trip out comes after his former friend and producer Naughty Boy, real name Shahid Kahn, attempted to reignite their feud which has rumbled on since last year. 

Having initially forged a close friendship after the handsome star left One Direction last August, Naughty Boy appeared to vow to launch Zayn's solo career. 

After working together at length, their relationship fell into disrepair when Zayn accused Naughty Boy of leaking one of his unfinished tracks and called him 'a fat joke'. 

No love lost: Having initially forged a close friendship after the handsome star left One Direction last August, Naughty Boy appeared to vow to launch Zayn's solo career

Out and about: He showed off his newly sheared head, with a bleached look over the top, while his smattering of designer facial hair was firmly in place

Now Naughty Boy has hit back and seemingly threatened to leak an original version of a track, writing a now-deleted tweet reading: 'Please don’t make me leak the original #likeiwould ha’.'

Additionally he seemed to allude to the fact that he also worked on Zayn's number one hit Pillowtalk as he wrote: 'Credit where credit's due' after referencing the track's producers, Make You Know Love – brothers Anthony and Michael Hannides

Despite his feisty allegations, the esteemed producer appeared to backtrack on his words, saying: 'this ain't about me.. its just about giving (Anthony and Michael Hannides) credit to for writing an amazing song, thats all.. bless. have a great day.' 

Not happy: Now Naughty Boy has hit back and seemingly threatened to leak an original version of a track, writing a now-deleted tweet reading: 'Please don’t make me leak the original #likeiwould ha’

Glum figure: Zayn looked extremely serious as he headed into the building 

Just one day before his tracksuited outing, Zayn maintained his moody persona as he headed out in New York on Wednesday.

The Brit singer cut a solemn figure as he rocked head-to-toe green for the solo outing, but did show off his cheerier side with a heartfelt message to his fans on Twitter.

Zayn layered a green jacket over a zipped-up hoodie and matching trousers in the same colour palette.

Cheer up! Just one day before his tracksuited outing, Zayn maintained his moody persona as he headed out in New York on Wednesday

The ex boybander added white sneakers, while he pulled up the hood of his sweatshirt for his city stroll.

The star, who regularly changes his hair do, flashed a glimpse of his shaven head as well as his tattoos.

While Zayn looked a little glum, he reserved his cheer for Twitter, taking to his page on Wednesday to thank his dedicated fans for all their support with his new album. 

'Zquad thank you dreams coming true right now,' he wrote. 

See more on Zayn Malik as he cuts a glum figure as he heads out in NYC

It's not easy being green: He stood out in his one colour ensemble as he hit the streets in his new favourite city

Favourite colour? Zayn layered a green jacket over a zipped-up hoodie and matching trousers in the same colour palette

Edgy sense of style: The star, who regularly changes his hair do, flashed a glimpse of his shaven head as well as his tattoos

Where's Gigi? Zayn stepped out without his model girlfriend Gigi Hadid, who he's been staying with in NYC

Zayn's first solo album Mind Of Mine was released this week, exactly one year after his shock departure from One Direction.

The star's 'Zquad' has ensured his debut solo effort soars in the charts, with the record set to knock Adele of the top of the album charts at the weekend after her global success with 25. 

The Bradford-born singer is currently sitting 5,000 sales ahead of Adele on the UK's Official Album Chart, while the album's debut single, Pillowtalk, has been the fastest selling single of the year so far.

Thanks guys! While Zayn looked a little glum, he reserved his cheer for Twitter, taking to his page on Wednesday to thank his dedicated fans for all their support with his new album

Exciting time: Zayn's first solo album Mind Of Mine was released this week, exactly one year after his shock departure from One Direction

Number one? The star's 'Zquad' has ensured his debut solo effort soars in the charts, with the record set to knock Adele of the top of the album charts at the weekend after her global success with 25