The United States submitted a formal proposal to Russia for cooperation on missile defense, seeking to defuse an issue that has increased tensions between Washington and Moscow. Addressing another contentious issue, the US also submitted on Wednesday a separate proposal that it hoped would discourage Moscow from withdrawing from a key European arms control treaty. Both issues have contributed to US-Russian relations worsening to the lowest point since the Cold War. The proposals had been discussed in negotiations between the two nations, but Russia insisted on having them in writing before continuing talks. US and Russian officials declined to release the documents. US Secretary of State Condoleezza Rice and Russian Foreign Minister Sergei Lavrov are expected to discuss them Monday ahead of the Annapolis conference.