As Chris Petersen, head of the supposedly 600-member Marxist-Leninist party of the Netherlands, Pieter Boevé travelled to Beijing more than two dozen times and met Mao Zedong. He was also welcomed with open arms in Albania by Enver Hoxha, and in the eastern bloc capitals of Europe.

"In fact we had at most a dozen members, none of whom had the faintest idea of the truth," Mr Boevé said yesterday from his home in the seaside resort of Zandvoort. "The whole thing was a hoax, set up by the secret services to learn all they could about what was going on in Marxist Peking."

The Mao regime was so impressed by the revolutionary zeal of Mr Petersen/Boevé and his MLPN that it gave him regular briefings on the chairman's latest thinking at the Chinese mission in The Hague. Beijing even funded the non-existent party's newspaper, De Kommunist, which was written entirely by Dutch secret service (BVD) agents.

"We took everybody in," Mr Boevé said proudly yesterday. "As far as I know, the MLPN was the only wholly fake radical party to have existed, and certainly the only one to have really worked. We passed inside information on every Maoist policy nuance to all the western intelligence forces. It was a wonderful adventure."

Mr Boevé was first recruited by the BVD in 1955 when he visited a World Student Congress in Moscow. Soon after, he was invited to China, then still the Soviet Union's ally, for a similar communist youth junket. After the Sino-Soviet split of the early 1960s, the Chinese began courting western communists and, egged on by the BVD, Mr Boevé played along.

"I was invited to Peking for a month-long course on the wisdom of Chairman Mao," he said. "It was quite a baptism of fire. I hadn't read a great deal of Marx or Lenin at that stage, let alone Mao. But I soon got very proficient. I could spout for hours."

The foundation of the MLPN was announced by De Kommunist in 1969. Its main role was to undermine the official Dutch Communist party, the KPN, by denouncing its deviant beliefs and unreliable conduct, and to garner information on - and gain access to - the Maoist elite in Beijing.

In the latter task, it was successful beyond the BVD's wildest dreams. "They adored us," Mr Boevé said. "I was invited to all the big events - Army Days, Anniversaries of the Republic, everything. There were feasts in the Great Hall of the People and long articles in the People's Daily. And they gave us lots of money."

Most European Maoist groups, unable to keep up with an endless string of purges and policy about-turns, had lost faith by the mid-1980s, and the MLPN gradually began winding down its activities. But as late as 1989, after the Tiananmen student uprising, Mr Boevé was invited to Beijing to praise the regime's crackdown.

The existence of Project Mongol, as it was dubbed by the BVD, was successfully kept secret until this September, when another former agent, Frits Hoekstra, published a book about the service's glory days. It caused something of an uproar in the Netherlands, a country where a fair few genuine former radicals now occupy leading positions in public life.

Mr Boevé, who was never a salaried spy and who, despite his extra-curricular activities, rose to become headteacher of a top Dutch grammar school, said he was at first unwilling to have his name revealed. "My family knew, but no one else," he said. "As far as my friends and former colleagues were concerned, all my travel was to do with educational exchanges."

Since the revelations about his former life as one of the west's most productive spooks, Mr Boevé said reactions have varied from shock and disbelief - "How can we ever trust you again?" - to mild amusement. "My fellow members of the Zandvoort town council call me 007," he said. "I don't mind. I'm satisfied with what I've done with my life. I've travelled the world at someone else's expense, and I feel did my bit. And it was certainly fun."