BEIJING, January 20: China today assured the United States that all transfers of anti-ship cruise missiles to Iran have been halted along with the technology to upgrade missiles already with Tehran, US Defence Secretary William Cohen announced here."It was the very clear message that no sales will go forward, no transfers - period - to Iran. That would include those missiles that have been contracted for before," Cohen told media persons after a meeting with Chinese President Jiang Zemin."That was very significant from my point of view," he said after a 65-minute meeting with Jiang which wrapped up his three-day visit to China."I think the two assurances will go a long way to building upon the very cooperative relationship that we are developing," he was quoted as telling journalists accompanying him to Tokyo.During his talks with top Chinese leaders, Cohen also proposed talks between officials from nuclear rocket forces of both the countries to minimise the risk for "accident" or "miscalculations" involving these weapons.Cohen said the Chinese side had agreed to look into his offer for dialogue and exchanges between the US strategic command and Beijing's second artillery, which are in-charge of the nuclear arsenals of their respective countries.This, Cohen said, would allow both sides to focus on the issue of nuclear safety so as to reduce the risks posed by nuclear weapons.Describing his visit to China as "productive", Cohen said the trip had enabled both sides to take "modest but steady" steps to enlarge their current areas of contact and cooperation.Cohen, however, ruled out the withdrawal of over one lakh US troops deployed in the Asia-Pacific region by saying the presence of American troops in the region had acted as a "stabilising factor" in the area."For half a century, America's military presence and engagement has been the basis for stability in East Asia and it has ensured that the Pacific Rim is lapped by warm, calm waters," Cohen said claiming that "no nation has benefitted more than China from the stabilising effect of American military engagement in Asia".He said the theatre missile defence (TMD) system was essential for the security and protection of American troops who were in a forward deployed posture in the region.Cohen stoutly defended the US-Japan security alliance and stressed that this was not targeted against a "third country".Commenting on China's oppositon to the alliance, he said, "What these guidelines do not do is seeking to isolate any nation in the region. On the contrary, they are designed to expand stability for the benefit of all nations.""The US-Japan security alliance will be as important to Asia's future as it has been to its past," he said, adding it had also enhanced confidence in the region by increasing the extent to which Japanese and American security structures were integrated.On the thorny issue of Taiwan, Cohen said the Clinton administration would adhere to the "One China" policy and follow the three joint communiques on the question of supply of weapons.