Meghan jets out to New York to watch her friend Serena Williams play

The Duchess of Sussex flew on a commercial plane to New York today to watch her friend Serena Williams play in the final of the US Open.

Meghan is believed to be flying solo across the Atlantic – leaving Harry and their four-month-old son Archie in Windsor – although a security team is said to be with her.

The royal is likely to have flown first class for her two-day trip to the US to watch the match, just days after her husband spoke out about sustainable travel at an environmentally-friendly tourism event in Amsterdam. 

And last month he is understood to have given a passionate barefoot speech about saving the planet at Google’s £16million climate change summit in Sicily.

Meghan’s journey to New York and back is expected to generate 986kg of carbon dioxide. 

She will cheer on Williams, 37, against Bianca Andreescu in Queens tomorrow as the former world number one again tries to equal the all-time grand slam record.

The Duchess, who also watched Williams at Wimbledon in July, flew out following the row over the eco-warrior couple taking four trips by private jet in 11 days last month. 

Meghan stayed up to watch the semi-final, which ended at 1.30am today UK time, and is thought to have boarded a flight in London at about 8.30am this morning.   

Meghan is expected to return to Britain on Sunday. A source told The Times: ‘It is a last-minute trip. Excited to support her friend, and then come back.’ 

She is said to have been thinking about travelling across the Atlantic to attend the final at Arthur Ashe Stadium since Williams won her quarter-final on Wednesday.

This is Meghan’s first trip to New York since her baby shower in February when she partied for five nights at a £57,000-a-night penthouse with her celebrity friends. 

The party, which caused disquiet in Britain due to its eye-watering estimated total bill of £330,000, was hosted by Williams and her long-standing friend Jessica Mulroney.

Meghan flew to and from the US on that occasion on a private jet with her close friend Amal Clooney, who paid for the 13-hour round trip which cost £13,277 an hour.

Meghan first met Williams at a Super Bowl party in 2010, and their friendship is thought to have quickly evolved through frequent phone calls and texts. 

After becoming Prince Harry’s girlfriend and then a Duchess, Meghan is said to have leaned on Williams for mentoring on how to handle the media.

Williams, who attended their wedding in May 2018, said last year they had ‘known each other for a long time, but we really are relying on each other a lot recently’.

The couple, who live at Frogmore Cottage in Windsor, enjoyed a week-long trip to Ibiza and a long weekend in the south of France with Sir Elton John last month. 

The Sussexes have been under fire for taking private flights after previously claiming they will have a maximum of two children to avoid damaging the environment.

Their son Archie, who was born at Portland Hospital in London on May 6 and is seventh in line to the throne, is four months old today. 

Some Twitter users criticised Meghan’s decision to fly again today, with one saying: ‘Another flight, for the few not the many, hey Meghan.’

Another tweeted: ‘Commercial! Thought Hazz (Harry) was concerned for his family’s safety that the little poppets had to travel private.’

Royal expert Robert Jobson told MailOnline: ‘The Duchess has a fashion launch next Thursday and is then going to South Africa on a historic first trip with Archie.

‘She clearly feels it is fair enough to take a social trip to see her friend play in a tennis final before stepping back into the public spotlight of official engagements.’

There had been rumours that the Sussexes would be joining the monarch at Balmoral in the Scottish Highlands this week with their baby son Archie.

But while most of the Royal Family have made the long trek up to Aberdeenshire, Harry and Meghan actually have no plans to fly to Scotland at all.

Sources close to the couple insist that the decision should not be seen as a ‘snub’ – and Harry only rarely goes up to the Queen’s Deeside estate nowadays.

They flew to Ibiza by private jet on August 6 for Meghan’s 38th birthday. Days later, they flew to Nice on a £15million Cessna plane described as the ‘pinnacle of luxury’.

Sir Elton said he paid for their flights to his holiday home and made an ‘appropriate contribution’ to a carbon footprint fund to offset the environmental impact.  

Earlier this week, Harry defended his use of private jets, claiming he needed them for his family’s safety – despite urging the public to cut their carbon footprint. 

He took a scheduled flight to Amsterdam this week to promote Travalyst, a scheme for environmentally-friendly tourism.

Speaking at the event, the prince refused to apologise for his recent private flights, saying: ‘I spend 99 per cent of my life travelling the world by commercial.

‘Occasionally there needs to be an opportunity [to fly privately] based on a unique circumstance to ensure that my family are safe – it’s as simple as that. 

‘For me it’s about balance. It’s not a decision I would want to take, but if I have to do that, I will ensure that I balance out the impact that I have.’ 

Harry dismissed concerns over his carbon footprint by insisting that he ‘offsets’ his emissions by donating to renewable energy incentives and planting trees. 

The row was worsened for the couple when the Duke and Duchess of Cambridge were seen flying with their children on a budget flight from Norfolk to Scotland.

Decisions about the most effective, economical and safe way to travel are taken by a royal visits committee.

Despite his comments, analysis of Harry and Meghan’s known international flights since their wedding shows six of the ten return trips they took were by private jet.

Harry dismissed concerns over his carbon footprint by insisting that he ‘offsets’ his emissions by donating to renewable energy incentives and planting trees.

Meghan’s visit to watch Williams at Wimbledon in July was marred over a row that saw a tennis fan told off by her security team for attempting to take a selfie with her.

The fan, Hasan Hasanov, said he was actually trying to get a picture of himself with Roger Federer in the background and did not realise Meghan was in front of him. 

Early this morning, Williams steamrollered Elina Svitolina 6-3 6-1 in the semi-final to win at 1.30am UK time to reach her fourth major final since becoming a mother.

She lost the previous three, including two Wimbledon finals, meaning she remains tantalisingly one short of Margaret Court’s record tally of 24 grand slams.

Next Thursday, the Duchess will carry out her first official public engagement since the birth of her son – launching a high street clothing range in aid of charity.

Meghan will proudly show off the collection created by Jigsaw, John Lewis and Partners, Marks and Spencer and her designer friend Misha Nonoo.

Since the birth of Archie on May 6, she has been caring for her child – although she has been seen privately attending a polo match where husband Harry was playing. 

Meghan’s friend Ms Nonoo is credited with introducing Harry to his future wife via a blind date and she had a VIP seat at the royal wedding at Windsor Castle.

Meanwhile the Duke and Duchess hired a team of Hollywood publicists to promote their charitable foundation which brings together their philanthropic ventures.

Sunshine Sachs, which Meghan has used before, prides itself on aggressive dealings with the media and will manage publicity for the couple’s Sussex Royal initiative.

The development bolsters claims Harry and Meghan plan to focus much of their professional and personal lives in the US, where Los Angeles-born Meghan is from. 

After the news of Meghan’s flight was revealed this morning, a Kensington Palace spokesman told MailOnline: ‘We wouldn’t comment on private travel.’

A US Department of State spokesman declined to comment on whether Meghan would receive diplomatic protection and how much notice it had of the trip.

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