Donald Trump has attacked the late former first lady Barbara Bush in a newspaper interview a day after posting a satirical alt-right meme of ex-vice-president Joe Biden on Twitter.

“I see that you are on the job and presidential, as always,” Mr Biden responded to the tweet, which sits pinned to the top of the president’s Twitter profile. The video in question sends up Mr Biden’s apology after he was accused of inappropriate conduct towards women while on the campaign trail, and was circulated by Donald Trump Jr earlier on Thursday.

Mr Trump then made a stop in Calexico, California, to inspect construction work on his US-Mexico wall after rowing back on his threat to close the border, the trip providing a timely change of focus for the president after thousands of protesters campaigned outside the White House and in New York’s Times Square to demand the release of the Mueller report in full.

While in southern California, Mr Trump heard from officials who praised his leadership and promised to build some 400 miles of border wall in the next year and a half.

Mr Trump, during a round table with Border Patrol officials, said that the US has no more room for immigrants — and thanked Mexican officials for what he described as new efforts to stop migrants from making it to the US-Mexico border.

Trump prototypes for Mexico border wall demolished in California Show all 20 1 /20 Trump prototypes for Mexico border wall demolished in California Trump prototypes for Mexico border wall demolished in California The prototypes for President Trump’s border wall are being demolished. AP Trump prototypes for Mexico border wall demolished in California The US Customs and Border protection had built the eight 30-foot tall steel and concrete models near San Diego on the US-Mexico border. Reuters Trump prototypes for Mexico border wall demolished in California A 2018 report from the Government Accountability Office found that the construction challenges presented by the four concrete models would be “extensive” and those presented by two of the other models would be “substantial”. Reuters Trump prototypes for Mexico border wall demolished in California It was intended that Mr Trump would choose his favourite of the designs after testing had been completed. AFP/Getty Trump prototypes for Mexico border wall demolished in California The President is yet to comment. AFP/Getty Trump prototypes for Mexico border wall demolished in California Each prototype cost $300,000 to $500,000 to build and they are being knocked down in order to make way for the San Diego Secondary Wall project which will see up to 14 miles of barrier being built to support the existing steel border fence. AP Trump prototypes for Mexico border wall demolished in California The new barrier will not employ the design of any of the prototypes, instead being built of the favoured steel bollards which make up the current section of the wall at San Diego. Reuters Trump prototypes for Mexico border wall demolished in California The new secondary barrier being built near San Diego. Reuters Trump prototypes for Mexico border wall demolished in California The rubble of one of the demolished prototypes. Reuters Trump prototypes for Mexico border wall demolished in California A steel wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A wall prototype made from a mix of steel and concrete AFP/Getty Trump prototypes for Mexico border wall demolished in California A wall prototype made from a mix of steel and concrete AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A steel wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A digger approaches the prototype wall AFP/Getty Trump prototypes for Mexico border wall demolished in California Aerial view of the wall prototypes at the US-Mexico border after they were torn down AFP/Getty Trump prototypes for Mexico border wall demolished in California An aerial view showing Tijuana, Mexico on the left and the demolished wall prototypes on the right AFP/Getty

The White House, prior to Mr Trump's visit to the border, hailed the 2-miles of fencing there as the first completed section of the president's border wall.

But, Mr Trump cannot take full credit for the construction: Border barriers have existed there for decades, and plans for the recent renovations first began to develop during the presidency of Barack Obama.

Follow along below for our coverage as it happened