With the ceasefire in place, and UN peacekeepers monitoring the border, Iran and Iraq sent their representatives to Geneva, Switzerland, to negotiate a peace agreement on the terms of the ceasefire. However, peace talks stalled. Iraq, in violation of the UN ceasefire, refused to withdraw its troops from of disputed territory at the border area unless the Iranians accepted Iraq's full sovereignty over the Shatt al-Arab waterway. Foreign powers continued to support Iraq, which wanted to gain at the negotiating table what they failed to achieve on the battlefield, and Iran was portrayed as the one not wanting peace. Iran, in response, refused to release 70,000 Iraqi prisoners of war (compared to 40,000 Iranian prisoners of war held by Iraq). They also continued to carry out a naval blockade of Iraq, although its effects were mitigated by Iraqi use of ports in friendly neighbouring Arab countries. Iran also began to improve relations with many of the states that opposed it during the war. Because of Iranian actions, by 1990, Saddam had become more conciliatory, and in a letter to the now President Rafsanjani, he became more open to the idea of a peace agreement, although he still insisted on full sovereignty over the Shatt al-Arab.