April crude oil prices were on a higher track during the initial morning hours, drafting support from a boost in risk-taking sentiment and reports of growing participation for today's Greek debt swap deal. Some traders indicated that optimism that Greece will avoid a disorderly debt default, along with ideas that the US Fed maybe considering more quantitative easing measures contributed to the early gains in crude oil. Meanwhile, the global crude oil market could see some modest tightening as the month progress as Royal Dutch Shell lets contracts of Iranian oil expire and looks elsewhere for supply. The latest read on the US supply situation showed a slightly smaller that expected build of 832,000 barrels last week.