The White House has announced plans to build a $200m (£151m) new ballroom, fulfilling an often-repeated desire of US President Donald Trump.

The new ballroom will be built alongside a "modernised" East Wing of the White House, which currently houses the offices of First Lady Melania Trump and other key White House posts.

The money will be donated directly by Trump and other so-far anonymous donors, with work beginning in September, according to Press Secretary Karoline Leavitt.

Trump has repeatedly promised to build a "beautiful" ballroom at the White House, and in 2016 offered to pay $100m during Barack Obama's administration - which the then-President rejected.

In a briefing for reporters at the White House on Thursday, Leavitt said that the "much needed and exquisite addition" to the White House will be approximately 90,000 sq ft (8,360 sq m) with a seating capacity of about 650.

Many formal White House functions are held in the White House's East Room, which can seat approximately 200 people.

The new ballroom, Leavitt added, would also eliminate the need for a "large and unsightly tent" to be installed for state dinners and other large events, which sometimes include world leaders.

According to Leavitt, construction is expected to be completed "long before" the end of Trump's term in office in January 2029.

"The President and the Trump White House are fully committed to working with the appropriate organisations to preserving the special history of the White House, while building a beautiful ballroom that can be enjoyed by future administrations and generations of Americans to come," Chief of Staff Susie Wiles said in a statement.

Renderings provided by the White House show that the ballroom will be similar architecturally to the rest of the White House, with a lavish interior including chandeliers and ornate columns.

"The White House has a history of expansion to accommodate the changing needs of the nation's chief executive," Leslie Greene Bowman, who has served under four presidents on the Committee for the Preservation of the White House, told the BBC.

"I hope and trust that any proposed changes will honor and preserve the existing walls that have witnessed so much history. They are precious vessels of our legacy as a democracy."

Offices housed in the East Wing of the White House adjacent to the construction - including that of First Lady Melania Trump - will be temporarily re-located.

President Trump has repeatedly voiced his wishes for a new ballroom as part of renovations to the White House, which has already seen the installation of two large flagpoles, new gold decorations in the Oval Office and the bulldozing and paving over of the famed Rose Garden.

"There's never been a President that's good at ballrooms," Trump said at an event at the White House on Thursday. "I'm good at building things."

Trump added that "they've always had to get tents" for large events at the White House, which he described as a disaster. "It's not a pretty sight."

Earlier this week during a Scotland meeting with European Council President Ursula Van der Leyen, Trump told her that "we're building a great ballroom at the White House"

"No president knew how to build a ballroom," Trump said while sitting in another ballroom at his Turnberry golf resort. "I could take this one, drop it right down there, and it would be beautiful."

In 2016, when on the campaign trail during the administration of Barack Obama, Trump famously offered to contribute $100m for the construction of a new ballroom for the White House to use to host events.

At the time, then-Press Secretary Josh Earnest said that the suggestion was "not something that was at all seriously considered".

"I'm not sure that it would be appropriate to have a shiny gold Trump sign…on any part of the White House," Earnest told reporters.