Trump to postpone London visit until 2018

President Donald Trump will no longer be visiting London in his first year as president, a senior White House official confirmed to ABC News today.

The official cited a "scheduling conflict" as the reason behind the change, and said the White House has gotten in touch with the British government to iron out plans for a visit in 2018.

Downing Street did not respond to multiple requests for comment.

During the president's bilateral meeting with British Prime Minister Theresa May at the G-20 summit on Saturday, Trump said he still planned to move forward with the visit but dodged on providing any details about timing.

"We'll work that out. We will be going to London. We'll be going to London," Trump told reporters.

"There is no country that could possibly be closer than our countries. We have been working on a trade deal which will be a very, very big deal, a very powerful deal, great for both countries and I think we will have that done very, very quickly," added Trump during his 50-minute session with May.

The confirmed postponement follows a prolonged back-and-forth between the White House and Downing Street amid the increasingly thorny political issues around hosting Trump for a lavish state visit.

Queen Elizabeth II's speech on June 21 raised eyebrows when she didn't mention Trump by name in her address to parliament, which mentions all planned state visits. The Queen only indicated that King Felipe and Queen Letizia of Spain would be visiting in July 2017.

Downing Street said only that the invitation, which was given by May on behalf of the Queen, remained unchanged.

The president attacked London's Mayor Sadiq Khan over Twitter just last month, accusing Khan of downplaying the terror attack on London Bridge and Borough Market.

"At least 7 dead and 48 wounded in terror attack and Mayor of London says there is "no reason to be alarmed! " tweeted Trump.

Trump based his Twitter comment on Khan's BBC television appearance after the attacks, where Khan said Londoners can expect an increased police presence, and that there would be no "reason to be alarmed" as the "police would make sure they were safe as they could possibly be."

The mayor's office dismissed the president's Twitter post, issuing a statement that Mr. Khan was too busy to reply to the U.S. president.

"He has more important things to do than respond to Donald Trump's ill-informed tweet that deliberately takes out of context his remarks urging Londoners not to be alarmed when they saw more police - including armed officers - on the streets," his office said in the statement.

Trump also faced criticism when the Times of London published an article on April 15 indicating that the president had requested a ride with the Queen in the state's gold-plated carriage during his slated visit to the U.K. in October.

While the tradition of world leaders taking a carriage with the Queen from the Royal Mews to Buckingham Palace wasn't unusual, Trump's plans prior to an official tour date riled up U.S.-U.K relations, in spite of the White House saying it was "completely false."

Alexander Mallin and Benjamin Gittleson contributed to this report.