GENEVA (Reuters) -The United States, Britain, Norway and Germany plan to submit a motion to the U.N. Human Rights Council to set up an investigation into alleged atrocities in Sudan, a draft motion showed on Friday. Bloodshed, violence and displacement have escalated since fighting between the army and the paramilitary Rapid Support Forces erupted in April, driving Sudan to the brink of civil war. The RSF has denied accusations by conflict monitors, rights groups and witnesses that it is behind attacks on civilians, while saying any of its soldiers found to be involved would be brought to justice.