PHNOM PENH, May 26 (AFP) - Sri Lanka's government on Wednesday claimed key progress on the Cambodian leg of a diplomatic offensive aimed at hitting Tamil Tiger weapons buying networks in Southeast Asia. A delegation led by Foreign Minister Lakshman Kadirgamar said a halt in Liberation Tigers of Tamil Eelam (LTTE) arms shipping through Cambodia, Thailand, Laos and Vietnam would mark a turning point in Colombo's fortunes. "If weapons stopped coming from this part of the world, it would starve the LTTE of supplies," spokesman for the 10-member delegation Ravinatha Aryasinha told AFP. "The approach here has been not to complain, but to seek the help of friends in the region. And after this we go back reassured," Aryasinha said following talks with Cambodia's King Norodom Sihanouk. Talks have also been held with Foreign Minister Hor Namhong and Deputy Prime Minister Sar Kheng. He described the diplomatic tour -- which has so far taken in Laos, Vietnam and Cambodia and moves to Thailand on Thursday -- as part of Colombo's attempt to "nudge" the Tamil Tigers towards entering into negotiations with the government. "The Southeast Asian region is now more stable than ever, and we hope this will lead to improvements in controls on weapons exports," he said. According to intelligence sources and reports on the LTTE's extensive and advanced overseas logistics operations, weapons buying is now centered in Southeast Asia where arms can be bought relatively cheaply and easily. Other sources of LTTE weapons are reported to include Pakistan and Afghanistan. Cheap weapons availability is also expected to increase in Cambodia with the government about to embark on an ambitious programme of military demobilisation following the end of their two decade-old battle against the Khmer Rouge. Aryasinha said LTTE networks were shoppping in the region for supplies ranging from fuel to SAM anti-aircraft missiles. These supplies are then shipped to waters off the coast of Sri Lanka and collected by Tiger speedboats. The LTTE is leading a drawn-out campaign for independence in the island's northern and eastern regions where the minority Tamils are concentrated. More than 55,000 people have been killed in fighting in the past 27 years. While the Sri Lankan Foreign Minister said assurances had been given by Cambodia that officials here "will keep an eye open" for Tamil Tiger activities, analysts say Colombo's forces are likely to face Cambodian-sourced weapons for some time. "Buying weapons and shipping is easy from countries such as Cambodia, where corruption in law enforcement and customs controls remains a widespread and accepted practice," explained a western diplomatic source who declined to be named. "And by all accounts the Tigers are pretty savvy businessmen when it comes to the arms trade: this a difficult combination to bust, and Cambodia has other priorities," he added. The Sri Lankan delegation, however, was upbeat about the tour and discussions on boosting cultural and trade ties they described as "a new chapter" in ties with Cambodia, even if their bloody civil appears far from over.  