Russia has rejected calls from the United States and Western Europe for greater sanctions against Syria for its violent crackdown on protesters. Russian President Dmitry Medvedev said on Monday that there is no need for additional pressure on Syria. He said any United Nations resolution on Syria must be tough but balanced.Russia has veto power in the UN Security Council and can stop the passage of any resolution against Syria. Last week, Russian President Dmitry Medvedev indicated that Moscow may be willing to consider a UN resolution that sends a strong message to Syrian President Bashar al-Assad.UN High Commissioner for Human Rights Navi Pillay said on Monday during an address to the Human Rights Council that 2,600 people have been killed in the Syrian uprising in the last six months. The United States has condemned the killing of prominent Syrian human rights activist Ghiyath Mattar, who died last week while in the custody of Syrian security forces.