Turkish Prime Minister Recep Tayyip Erdogan has expressed support for Britain\'s efforts to put pressure on Syria at the UN Security Council, Prime Minister David Cameron\'s spokesman said Monday. The British leader called Erdogan late Sunday to congratulate him on his re-election, and the two men expressed concern about the security crackdown in Syria and agreed on the importance of a unified international response. \"Prime Minister Erdogan welcomed the UK\'s efforts to put pressure on the regime through a Security Council resolution and they agreed that Britain and Turkey should work hand in hand to achieve this,\" the spokesman said. He said the two leaders noted that \"the situation had deteriorated markedly in the last week and agreeing that the violence was a cause of deep concern\". \"They agreed on the importance of international unity in response to a crisis that is increasingly dangerous for the Syrian people and the region,\" he said. Britain, France, Germany and Portugal are seeking support for a UN Security Council resolution condemning the Syrian crackdown on anti-regime protesters, but have faced opposition from South Africa, Brazil and India. Erdogan is a personal friend of Syrian President Bashar al-Assad but he has condemned the actions of Assad\'s security services, which have prompted a flood of refugees over the border into Turkey.