WASHINGTON, May 20 (AFP) - A soon-to-be-released report on alleged Chinese espionage will show "megatons" in damage to US national security, Senate Republican Majority Leader Trent Lott told reporters Thursday. And Washington cannot ignore the charges when considering trade ties with China as well as its accession into the World Trade Organization, he said, without firmly opposing Beijing's entry. A special House of Representatives committee led by Republican Representative Christopher Cox has been probing the matter and will issue its report next Tuesday, according to a panel spokesman. Lott warned that any trade deal China -- which he charged with dumping products on US markets, improperly transferring technology, and human rights violations -- would need extensive monitoring and implementation. "I don't think we can trust the Chinese to live up to an agreement they make on trade," he said. "We should demand a good deal for us, and, this is more important, that it be enforced." Lott's comments came a day after Cox briefed him and other senators on the contents of the 700-page report, whose release has been delayed for months by fights between the Congress and President Bill Clinton's administration on what materials can safely be made public. The document will reveal that the espionage caused damage to US national security that "you almost have to measure in megatons." And he stressed that alleged theft of key nuclear weapons information from US nuclear laboratories "could be the biggest breach of national security of our lifetimes." Asked whether Congress would take legislative action in response to the report's revelations, Lott replied "yes," adding that Senate committees on intelligence, armed services, and energy were considering such action. Queried who should be held accountable for reported failure to act after suspicions of spying surfaced in 1996, Lott said "something must be done about it, somebody's head must roll," but would not name specific culprits. Asked to assess President Bill Clinton's policy of engagement, Lott criticized it as "an abysmal failure." Major US dailies have reported that China stole key codes and designs, compromising virtually every nuclear weapon in the US arsenal, including the W-88 warhead and the neutron bomb. And Cox said Wednesday that the report would also address Chinese "acquisition of US technology that includes military hardware separate from nuclear weapons," such as radar-evading "stealth" technology. Asked whether espionage was not relatively common, Cox agreed but stressed that except for China "no nation has succeeded in stealing so much" nor used the data to target the United States with arms. Beijing has repeatedly denied the charges, and specifically the Cox report, and a Taiwan-born scientist fired from the Los Alamos National Laboratory in March for security lapses has yet to be formally charged.  