UBS says that Tullow Oil is in a comfortable financial position, and with catalysts "plentiful" in September, the broker keeps its buy rating on the Africa-focused oil giant."With the expectation of receiving $2.9bn cash for the sale of its Ugandan assets, coupled with growing cashflows from Jubilee, Tullow looks to be in a relatively comfortable position," the Swiss bank said.Furthermore, the broker thinks that drilling results from the Monteserrado well in Liberia and the long-awaited Zaedyus well in French Guiana should provide catalysts to the stock next month.However, after making minor adjustments to its net asset value assumptions (-4%), UBS cuts its target price for Tullow from 1,750p to 1,650p.Shares were 0.25% lower at 996.50p by 12:24.BC