Get Rows in SqlServer thoes are not mapping from other table

Question

One is Demand table and another table is VarientCountry i want only thoes varient from demand table which has no country mapping in varientcountry table

Demand Table

Id Varient Country
1     v1       India
2     v2       NULL
3     v3       Nepal
4     v4        Japan

VarientCountry Table

Id Varient Country
1    v1       India
2    v1       Uk
3    v2       China
4    v1       Indonisia
5    v3       Nepal
6    v4       Egland
7    v4       Null

I want Excepted Result like as

Id Varient Country
1     v1       UK
3     v2       China
6     v4       England