A bombshell from Gilbert & George

The themes of the veteran iconoclasts' new works are devastatingly simple: bombs, bombers, and bombing. They talk to Martin Gayford

In pictures: Gilbert & George

On Boxing Day this year, Gilbert & George went to a newsagent's to buy the morning paper.

Gilbert and George always wanted to be loved

"An old tramp – with a horrific smell – came in, dribbling," says George. "I felt it was so awful, someone going round like that at Christmas, that I said 'Good morning'. He said 'Good morning' back, and the shop assistant said, 'You don't know them.' He replied, 'They don't know me, but I knows them. They're famous artists and they've got an exhibition coming up at Tate Modern.' Extraordinary!"

Certainly, the fame of G&G seems to penetrate parts of the population that not all artists reach. But then, as they told me in their east London studio recently, many things have gone their way.

In the past it has been suggested that they were the godfathers of the Brit artists of the 1990s – now themselves established and occupying the middle of the art stage (G&G preferred, when asked, the role of "fairy godmothers"). "We even believe," says Gilbert, "that in some ways our vision of art has won. We used to be outsiders, and we aren't so much so now."

The fact that they are about to take over an entire floor of Tate Modern, plus other parts of the gallery, tends to confirm this claim. This G&G bonanza, modestly entitled Gilbert & George: Major Exhibition, will include a vast amount of work dating back as far as their early days.

It was in 1967 that George Passmore from Devon and Gilbert Proesch from the Italian Dolomites first met, at St Martin's School of Art, and decided that together they made up one artist. They first made an impression in the late 1960s as "living sculptures" – just themselves, alive in the gallery, their faces covered with metallic paint.

Now in their mid-sixties, they haven't changed much – though naturally they now look somewhat older, and in George's case, balder. Their capacity for exciting outrage remains undiminished – an exhibition last year entitled Was Jesus Straight? created, predictably enough, a furore. Even their suits are cut the same way as ever – weirdly out of fashion in the '60s and '70s, completely in tune with tailoring in the '90s, now looking slightly odd again.

G&G have moved with the times; they would argue that they have prophesied many developments. The notion of a breathing, sentient work of art was revolutionary 40 years ago. And their newest work, made especially for the exhibition, is, in a chilling fashion, equally attuned to the present age.

They have made six huge "Bomb Pictures" for the Tate show. Each consists of newspaper posters, collected and photographed over the past few years, containing the words "bomb" or "terror" or "bomber". "Together," Gilbert explains, "they create an amazing urban landscape. It's the best townscape an artist could do, with words. It's so simple and immediate. There's no need for us to say anything."

The six Bomb Pictures are horribly topical. G&G, like other Londoners, have to live with bomb threats and terror alerts; Aldgate Tube station, the scene of one of the July 7 attacks, is a few minutes' walk from their studio. But George says, "They are about past, present and future. London was bombed by Germans, IRA terrorists, and white supremacist homophobes as well as Al-Qaeda."

The pictures are intended as a commemoration, with the title of each – there is a 40-metre triptych entitled Bomb, plus Bombs, Bomber, Bombers, Bombing and Terror – written on a tombstone. "We think," adds George, "they are very powerful images. More and more they remind us of Lutyens – the Cenotaph, the war cemeteries."

The architecture of Lutyens is a characteristically unexpected G&G taste: they are connoisseurs of Edwardian London, which they have, equally characteristically, been exploring on foot, dressed in trademark G&G suits, still living sculptures after all these years.

London, in a complicated way, is their perennial subject. The point is made by the most surprising ingredient in the Bomb triptych. "Would you like to see the tallest living Londoner?" asks George. It turns out to be the London plane tree. G&G see the trees as a symbol of continuity. "In the past we've described them as our only living friends. We realised more and more that they are completely ignored, like the chewing gum on the pavement."

"Also," Gilbert adds with relish, "the seeds hanging down from the branches look like bullets, or hand grenades."

That is typical of the unique G&G angle on the natural world. So too is the fact that, after making the Bomb Pictures, they researched the plane tree (G&G were particularly taken with the story of the Persian ruler Xerxes falling in love with a plane, to which he wrote an ode). A couple of huge planes – which, true enough, I hadn't noticed – tower over their studio in Spitalfields. In a way, all their work comes out of their immediate environment: east London. But then, they have always claimed that the place where they live is the most representative possible of the current, globalised world.

"If a spaceship landed and they said we've got five minutes to report on a typical Earth planet place, where shall we go, we'd say Spitalfields, Commercial Street, Brick Lane." George said that 12 years ago, and it's getting truer all the time.

But they bridle at the idea that Spitalfields, their home of 40 years, is becoming gentrified – though its 18th-century buildings are now lovingly restored and glossy magazines hold parties in them. "We still have squatters, robbers, prostitutes, and crows eating dead rats in the middle of the street every morning," says George with pride. And how do they feel about that? "We're thrilled. It's inspiring!"

Although their environment may retain an edge, some of their ideas have become mainstream. Even the Conservative Party, which they have doggedly supported through triumph and disaster, looks as if it might make a comeback. What, I ask, do they make of David Cameron? "We're all for him," says George, "we very much agree with him about hugging hoodies."

"Cameron's very good looking," Gilbert puts in. "He's from Eton, like Jay Jopling. Etonians are a bit extreme – outsiders in a way. They have been taught to be superior."

"There is," George adds, "a certain confidence about anyone who's been to Eton – or to Borstal."

You might say that, without having attended either establishment, G&G have those qualities, too. None the less, they have their vulnerable points. And they feel their Tate show is already stirring up resistance.

"The knives are already coming out. The critics are sharpening them." And G&G – in common with absolutely everyone, I suspect, no matter how established and famous – are highly sensitive to bad reviews. "We always try to stop it getting to us," says Gilbert. "But it does get to us."

"We once had an interviewer who insisted that we provoked reviewers deliberately," recalls George. "So I leaned across the table and said, 'By the way, you must be the most stupid interviewer we've ever had, and terribly unattractive too!' He turned pale, he was just completely destroyed. So then I said, 'I was just testing.' "

Still, even if not all the reviews are glowing, this spring looks like being a bit of a triumph for these veteran iconoclasts. Do they worry that all this acceptance will destroy their status as avant-garde outcasts? Not at all, says George. "We always wanted to be accepted and loved, but we never were. We always dreamt that we would wake up, go out and buy the newspaper and read, 'Gilbert & George are the most extraordinary artists who do the most amazing pictures'."

"All we want," they once announced, "is total love." But the recognition demonstrated by this exhibition is quite a lot to be going on with?

"Yes," says Gilbert. "We admit it!"

Gilbert & George: Major Exhibition opens at Tate Modern, London SE1 (020 7887 8888), on Feb 15.