Modelled on Russian city names such as Leningrad and Stalingrad, Londongrad is a nickname given to London, from the fact that it has been, since the formal dissolution of the Soviet Union in 1991, the Western capital of choice for the Russian oligarchs.

For example, the following is from The Independent (London, England) of Monday 17^th October 2005:

‘LONDONGRAD’
From Russia with cash
It is not long since Russians came to Britain in two contrasting but equally exotic varieties. Category A were diplomats and spies—furtive men with an agenda that involved plotting red revolution. Remember the Russian naval attaché who slept with Christine Keeler who slept with John Profumo? Goodness, it was complicated then and it gave Her Majesty’s secret service no end of a headache.
Then there was the other type—dissidents, faces etched with suffering from their years in gulags. Both were rare finds in these islands and to meet one was as exciting as spotting a golden oriole would be to an ornithologist.
Now Russians are as common as starlings and no one follows them around as their only agenda is buying things—property, if they’re men and bits and bobs from Harvey Nichols if they’re women.
This invasion is not new. The owner of Chelsea football club, Roman Abramovich, is well known. But it may surprise some to know how many mini-Abramoviches have followed him. According to a report in today’s newspaper, 300,000 Russians live here, and wags have nicknamed it Londongrad and Moscow2.
Quite what lures rich Russians in droves to London may not be automatically apparent. Clearly, the presence of Karl Marx’s tomb in Highgate is no longer a draw.
Some say it is the “grand spaces” they can buy in Belgravia for a few million—a bagatelle for the entrepreneurs who did so well under Boris Yeltsin, but who have found life more taxing—literally—under Vladimir Putin. Combine that with the tax loopholes that allow rich Russians to live here cheaply, and Bob—or Vlad—is your uncle, or rather, your new neighbour.

And the following is from The Guardian view on the Ukraine crisis: calling time on Londongrad, an editorial about “the manner in which Britain has been cravenly complicit in the laundering of Russian oligarchs’ wealth”, published in The Guardian (London and Manchester, England) of Wednesday 23^rd February 2022:

A […] “Russia Report” of 2020, published by the intelligence and security committee, judged that oligarchs had become a corrupting force in British public life, using their money to make connections and exert undue influence. Again, the government response has been to delay and prevaricate.
As Vladimir Putin’s troops menace eastern Ukraine, and the world contemplates the possibility of a catastrophic war on European soil, the foot-dragging is inexcusable. Last week’s decision to shut down the so-called golden visa route for super-rich investors was welcome. But the exposure of the beneficiaries of dirty money already invested in Britain, and sweeping sanctions, should be a central part of any strategy to make Mr Putin realise the price of his aggression. “Londongrad”—a damning nickname which has been around for well over a decade—must finally be dismantled as a hub of Russian soft power and a safe conduit for Kremlin cronyism.

However, the name Londongrad—which has certainly been coined on separate occasions by various persons, independently from one another—had been used on at least two occasions before the collapse of the Soviet Union, and in reference to Communism:

1-: The following is from Senator Soaper Says:, published in the Montana Standard (Butte, Montana, USA) of Wednesday 28^th October 1931:

Though he recently came to the conclusion that Soviet Russia is the grandest place on earth, Bernard Shaw’s ¹ address for the time being is still Whitehall Courtsky, Londongrad.

¹ George Bernard Shaw (1856-1950) was an Irish playwright, critic, polemicist and political activist. A Socialist, he became an active member of the Fabian Society.

2-: The following is from an interview of the British actor George Cole (1925-2015), published in the Sunday Mirror (London, England) of Sunday 16^th September 1984:

In his very latest TV venture, Comrade Dad ², which begins rehearsals tomorrow, George also has some hilarious lines—although his character, a Communist Party sympathiser, couldn’t be further away from arch-capitalist Arfur.
“It’s set in 1999 in Britain after a Russian invasion. London has been renamed Londongrad,” says George.
“The only reason the invasion succeeded was that the Russians invaded on a Saturday afternoon. Everyone was out shopping or watching football.”

² Comrade Dad is a BBC satirical sitcom written by Ian Davidson and Peter Vincent, and directed by John Kilby. The pilot was broadcast in December 1984, and the series in January and February 1986.