David Harbour and Lily Allen sport matching topknots as they make red carpet debut as couple at Champions for Change Gala in NYC

They have just gone public with their romance in the past week.

But now it's out there, David Harbour and Lily Allen are ready to make their red carpet debut as a couple.

The American actor, 44, and the British singer, 34, arrived together for the Champions for Change Gala in New York City on Thursday night.

Together: They have just gone public with their romance in the past week. And on Thursday, David Harbour and Lily Allen made their red carpet debut at a charity fundraiser in New York

Together: They have just gone public with their romance in the past week. And on Thursday, David Harbour and Lily Allen made their red carpet debut at a charity fundraiser in New York

On Monday, Allen had posted to her Instagram that she was leaving her native UK to live in New York 'till after Brexit'.

She was already in the Big Apple where she was seen with the Stranger Things star after his hosting gig on SNL last Saturday night.

The pair were also snapped packing on the PDA on an outing in the city on Monday.

While their appearance at the charity fundraiser Thursday was more muted, they seemed relaxed and happy in each other's company knowing the eyes of the world were on them.

Couple: The American actor, 44, and the British singer, 34, posed for photos as they arrived for the Champions of Change Gala

Couple: The American actor, 44, and the British singer, 34, posed for photos as they arrived for the Champions of Change Gala

Simpatico: The two made a statement by styling their hair with matching half topknots

Simpatico: The two made a statement by styling their hair with matching half topknots

Pretty: Allen chose a patterned ankle-length frock with half sleeves for her night out. The floral-themed outfit had a Peter Pan collar with pink tie and she added black suede boots

Pretty: Allen chose a patterned ankle-length frock with half sleeves for her night out. The floral-themed outfit had a Peter Pan collar with pink tie and she added black suede boots

Dapper: Harbour went with an all black ensemble of two-piece suit and buttoned up shirt with shiny slip-on shoes

Dapper: Harbour went with an all black ensemble of two-piece suit and buttoned up shirt with shiny slip-on shoes

Allen chose a pretty patterned ankle-length frock with half sleeves for her night out.

The colorful floral-themed outfit had a Peter Pan collar with pink tie and she added a pair of black suede boots.

The pop star styled her short dark hair with a half topknot and accessorized with drop diamond earrings. 

Harbour, who also sported a half topknot, went with an all black ensemble of two-piece suit and buttoned up shirt with shiny slip-on shoes. 

Not hiding their feelings: The couple were seen together after Harbour's hosting gig on SNL last Saturday night. They were also snapped packing on the PDA on an outing in NYC Monday

Not hiding their feelings: The couple were seen together after Harbour's hosting gig on SNL last Saturday night. They were also snapped packing on the PDA on an outing in NYC Monday

Fun: David showed off his playful side as he leaned over and pulled a face at the camera while Lily smiled at him

Fun: David showed off his playful side as he leaned over and pulled a face at the camera while Lily smiled at him 

Event: The new couple looked more loved up than ever at the swanky event

Event: The new couple looked more loved up than ever at the swanky event 

Outfit: Allen completed her look for the evening with hoop earrings and a gold wristwatch

Outfit: Allen completed her look for the evening with hoop earrings and a gold wristwatch 

Romance: Allen and Harbour were first seen in public together in August when they were spotted enjoying a night out at the theatre in London

Romance: Allen and Harbour were first seen in public together in August when they were spotted enjoying a night out at the theatre in London 

Allen and Harbour were first seen in public together in August when they were spotted enjoying a night out at the theatre in London.

They also were seen on a date at the Hughie Fury vs Alexander Povetkin boxing match at London's O2.

Allen confirmed they are a couple on her Instagram Stories by posting images of the actor hosting SNL, and alongside a close-up of his bulging biceps she added the word 'Mine'. 

Allen has two daughters aged seven and six whom she shares with ex-husband Sam Cooper. 

Harbour previously dated Fantastic Beasts star Alison Sudol with whom he was last seen in April at the premiere of his movie Hellboy. 

Star-studded: Arbour and Allen posed on the red carpet next to (L-R) Sebastian Stan, Adam Schweitzer, Dianne Wiest and Katie Holmes

Star-studded: Arbour and Allen posed on the red carpet next to (L-R) Sebastian Stan, Adam Schweitzer, Dianne Wiest and Katie Holmes

Relationship: The couple seemed relaxed and happy in each other's company knowing the eyes of the world were on them

Relationship: The couple seemed relaxed and happy in each other's company knowing the eyes of the world were on them 

A-list: Lily looked in high spirits as she stood alongside Katie who looked stylish in a white, long-sleeved dress

A-list: Lily looked in high spirits as she stood alongside Katie who looked stylish in a white, long-sleeved dress 

Spotted: The romance first came to fans' attention when they attended a boxing match at London's O2 at the end of August, shortly after enjoying a trip to the theatre together

Spotted: The romance first came to fans' attention when they attended a boxing match at London's O2 at the end of August, shortly after enjoying a trip to the theatre together

Allen confirmed they are a couple on her Instagram Stories by posting images of the actor hosting SNL
Alongside a close-up of his bulging biceps she added the word 'Mine'

 Official: Allen confirmed they are a couple on her Instagram Stories by posting images of the actor hosting SNL, and alongside a close-up of his bulging biceps she added the word 'Mine'

Moving in together? Also on Monday, Allen posted to her Instagram that she was leaving her native UK to live in New York 'till after Brexit'

Moving in together? Also on Monday, Allen posted to her Instagram that she was leaving her native UK to live in New York 'till after Brexit'

David Harbour and Lily Allen make red carpet debut as a couple at Champions for Change Gala in NYC

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