The novelist Martin Amis has suggested that having white skin is still widely perceived as a core part of being English and says austerity has sent multiculturalism into decline.

In a documentary due to be broadcast this weekend on BBC4, Martin Amis's England, the writer suggests identity in is constructed differently in England from that in the US.

"The great thing about America is that it's an immigrant society and a Pakistani in Boston can say 'I'm an American' and all he's doing is stating the obvious," Amis says in the programme.

"But a Pakistani in Preston who says 'I'm an Englishman' – that statement would raise eyebrows, for the reason that there's meant to be another layer of being English. There are other qualifications, other than being a citizen of the country, and it has to do with white skin and the habits of what is regarded to be civilised society, and recognisable, bourgeois society."

According to Amis, the author of Lionel Asbo, State of England, a satirical novel in which a debt collector from inner London wins the lottery, much of contemporary England is characterised by "great tolerance". But in the "rough areas", Amis continues, "It's just as bad as it ever was".

In his documentary, Amis suggests multiculturalism has been "tremendously powerful for a good two or three decades" but is now in decline.

"It is probably weaker now than it used to be, because it's a luxury, that ideology," Amis says. "It's what you do when you have money in the bank and now there is no money in the bank, that kind of pan-tolerance will contract, because it's too altruistic for hard times."

Amis paints a picture of a nation still struggling to find its place in the world after suffering a "truly dramatic decline" in the middle of the 20th century, a decline made plain by being "humiliatingly brought to heel" by the US during the 1956 Suez crisis. Britain has accepted its status as a "second or even third echelon power", according to Amis, partly through the adoption of a mindset that has dulled the pain of lost power.

"In the later half of the 20th century, what helped England through was ideology of multiculturalism and anti-imperialism and levelism. So losing your empire didn't seem so bad because you didn't want an empire, you were ashamed of ever having had an empire, and that sweetened the pill of decline."

It is not the first time the novelist has addressed race in modern Britain. An interview he gave to the Sunday Times in 2006, where he confessed to a "definite urge" to suggest the Muslim community should "suffer … curtailing of freedoms … discriminatory stuff", ignited a slow-burning row that erupted into accusations of racism in 2007.

Amis strenuously denied the accusations. Writing in the Guardian, he said: "I do not 'advocate' any discriminatory treatment of Muslims. And I never have." The debate was about ideology, not race, he said.

In the BBC4 documentary, the novelist describes being obsessed by class during his teenage years, and being "ambitious to rise up from – you'd have to say – lower middle class origins". But he argues that the structure of English society has now completely changed.

"When I was of that age there was a vast gulf between state schools and public schools," he says. "And it was a class gulf. But now I think it's no longer a reflection of class, it's a reflection of money. Money has won. It had always won in America, but it's won in England, too. So if you put your son's name down for Eton it's because you can afford to do that, it's not because it's any class-granted right."

Amis, who explored the rise of turbo-capitalism in his 1984 novel Money, confesses to feeling somewhat adrift in the new Britain. "I have no nostalgia for the class society," he says, "but I have no great enthusiasm for the money society."

Another facet of British life in decline, according to Amis, is the monarchy, which he suggests is "nearing the end of the road".

"It's connected with our love of Upstairs, Downstairs, those country-house dramas," he said. "It's nostalgia for that class society; it's all connected."

The writer's remarks attracted criticism from Trevor Phillips, the former head of the Commission for Racial Equality.

"The problem with having a brain and a tongue as powerful as Martin Amis's is that if you start the latter without engaging the former you're going to end up in a ditch. Amis seems to have missed the point on both sides of the Atlantic," Phillips said.

He pointed out that London, Liverpool and Bristol had been multiracial cities for centuries and that almost all Americans would recognise their nation as an "immigrant mosaic".

He added: "Maybe next time Chelsea play Liverpool, he and I can have some fun debating with both home and away supporters – of all colours – what an English person looks like and how they should behave. I'd pay to see that."