The most strident critic of Prime Minister Thaksin Shinawatra attracted more than 40,000 people to a downtown park Friday and accused the Thai leader of buying obsolete jet fighters from Russia to reap a kickback of 3.5 billion baht (US$85 million; Ђ72 million). In a new allegation of corruption, publishing mogul Sondhi Limthongkul said that instead of purchasing modern planes from the United States or Sweden, Thaksin used his power to urge the air force commander to buy outdated, inefficient Russian planes. During a meeting last year, the foreign ministers of Thailand and Russia discussed the possibility of bartering Thai chickens for Russian warplanes. It was not immediately known whether a deal has already been concluded, and where the alleged kickback went. Police on Friday said they counted some 42,000 people coming through the gates of Lumpini Park, located in the heart of the capital's business district, where Sondhi has held earlier anti-Thaksin gatherings. But the rally, billed as a major showdown with Thaksin, failed to draw the half million people that Sondhi had hoped for in his continuing campaign to expose the wrongdoings of the government and oust the prime minister. Over the past two months Sondhi, once a close associate of the prime minister, has generated the biggest political crisis facing the once highly popular Thaksin in his nearly five years in power. Tensions, however, cooled over the past week after Thailand's revered king admonished Thaksin over his inability to accept criticism and tendency to strike out at opponents with lawsuits. Two days after King Bhumibol Adulyadej's advice, contained in a birthday speech, Thaksin dropped half a dozen lawsuits against Sondhi. But Sondhi said Friday that this would not blunt his drive. "Any day in the future until the day I die, if I accept any political position, and if I am no longer working in the media for you, if you see my face, spit in my face. You can take off your shoes and hit me in the face immediately," Sondhi told his audience. Sondhi repeated an earlier accusation that the prime minister's sister had used a military airplane to fly guests to her birthday and housewarming party in the northern city of Chiang Mai, reports the AP. N.U.