By Aileen Wang and Koh Gui Qing BEIJING (Reuters) - China's trade performance improved in June but still missed market forecasts, reinforcing expectations that Beijing will have to unveil more stimulus measures to stabilise the economy and meet its 2014 growth target. Imports also missed expectations, growing by 5.5 percent versus forecasts of 5.8 percent, although they returned to positive territory after a small drop in May. China's combined exports and imports edged up just 1.2 percent in first six months of the year, data showed on Thursday. Premier Li Keqiang said on Monday that economic growth quickened in the second quarter from the previous three months, but added that further modest government support measures will still be needed. Beijing has set an annual growth target of around 7.5 percent.