Insurer Aviva is on the rise on Thursday after it reported a better-than-expected 21% rise in its half-year profit.Aviva posted an IFRS operating profit of £1.27bn in the first six months of the year, up from £1.05bn a year ago and higher than forecasts of £1.15bn.The group also grew sales for the third consecutive quarter and improved the group's margin."We will continue to focus on customers and on the disciplined allocation of capital to ensure we grow Aviva profitably," said chief executive Andrew Moss."While we remain alert to the macroeconomic environment and risks in financial markets, Aviva has excellent franchises in proven growth markets and we are confident about the future." The interim dividend rises by 6% to 9.5p a share.Meanwhile, state-owned lender Royal Bank of Scotland (RBS) and insurance giant Aviva have confirmed that they rejig their strategic partnership.Under a new arrangement, Aviva will take over full ownership, replacing the current partnership arrangement and exclusively sell its products through RBS's branches, with both companies sharing the profits.