The Southern and Western Power don't like Nepalese politician visiting China. The global competition between West and China is, now, at its highest peak. During the Olympic games, West is helping Tibetian to raise their voice against Chinese policies on Tibet.
Being a Communist leader, China has become the first destination to give a official visit by the newly elected PM Prachanda. But our Southern and Western power don't take it as good signal. Nepal has always been a playground for India. And they don't like any new team to be invited to compete with them.  Lets hope this visit won't bring any sort of disaster in Nepalese politics again.
Bare in mind, before royal massacre and Madan Bhandari Assassination, both King Birendra and Madan Bhandari had recently visited China.