GENEVA, Dec 13 (Reuters) - United Nations Secretary-General Antonio Guterres called on Monday for new rules covering the use of autonomous weapons as a key meeting on the issue opened in Geneva. Negotiators at the U.N. talks have for eight years been discussing limits on lethal autonomous weapons, or LAWS, which are fully machine-controlled and rely on new technology such as artificial intelligence and facial recognition. But pressure has increased in part due to a U.N. panel report in March that said the first autonomous drone attack may have already occurred in Libya. "I encourage the Review Conference to agree on an ambitious plan for the future to establish restrictions on the use of certain types of autonomous weapons," Guterres said at the start of the five-day talks. The Convention on Certain Conventional Weapons has 125 parties including the United States, China and Israel. Some participating states such as Austria call for a total ban on LAWS while others including Washington have been more reticent and have pointed to potential benefits of such weapons which might be more precise than humans in hitting targets. Amnesty International and civil society groups are calling for countries to start negotiating an international treaty and will present a petition to negotiators later on Monday. "The pace of technology is really beginning to outpace the rate of diplomatic talks," said Clare Conboy of Stop Killer Robots. "(This) is a historic opportunity for states to take steps to safeguard humanity against autonomy in the use of force." France"s Disarmament Ambassador Yann Hwang, who is president of the talks, called for "key and vital decisions" to be taken this week. However, diplomats say the body, which requires consensus, is unlikely to reach agreement launching an international treaty, with Russia among others expected to oppose such a step. "There is not enough support to launch a treaty at this stage but we think some principles could be agreed for national implementation," said a diplomat involved in the talks. If no agreement can be reached, countries might move talks to another forum either inside or outside the United Nations.