shanghai dec 17 reuters  chinas bluechip stock index fell on friday notching its biggest weekly loss in three months as local and foreign investors worried about us and chinese regulatory restrictions and a global resurgence of covid19 cases  at the close the shanghai composite index ssec was down 116 at 363236 points  the bluechip csi300 index csi300 was down 159 the index lost 199 for the week its biggest weekly drop since midseptember  adding to tensions between the united states and china washington on thursday put investment and export restrictions on dozens of chinese companies including top drone maker dji accusing them of complicity in the oppression of chinas uyghur minority or helping the military read more  washington still has not decided whether to block more sales of us technology to chinese chipmaker smic 0981hk sources told reuters smic shares were up nearly 18 in hong kong on friday afternoon but have fallen nearly 13 this month read more  a subindex tracking ashares of semiconductor firms csih30184 slipped more than 3  foreign investors were net sellers of ashares with refinitiv data showing outflows of 136 billion yuan 21343 million through stock connect on the day nquotash nquotazk  the smaller shenzhen index szsc ended down 128 and the startup board chinext composite index cnt was weaker by 1608  around the region mscis asia exjapan stock index miapj0000pus was weaker by 067 while japans nikkei index n225 closed down 179  at 0700 gmt the yuan was quoted at 63696 per us dollar 001 weaker than the previous close of 6369  so far this year the shanghai stock index is up 46 and the csi300 has fallen 49 while chinas hshare index listed in hong kong is down 234 shanghai stocks have risen 192 this month