Mathrani said he felt “100 years of history is being relegated to the dustbin”.
He added: “The Crown Estate are like a brick wall covered with polystyrene politeness.
“We would like the King to persuade the Crown (Estate) to talk to us, be reasonable and have a discussion.”
His wife, and restaurant co-owner, Namita Panjabi, said: “Veeraswamy have catered twice at Buckingham Palace for the late queen.
“The first time was in 2009 when president of India visited, secondly in 2017 when India celebrated her 70th year of independence.
“It is astonishing that we are being asked to close after all of this. Along with Hamleys and Liberty, we are the oldest tenants on Regent Street.”