H1B employer forcing to sign leave notice on bench

[myh1bquery]

Urgent : H1B employer forcing to sign leave notice on bench

Hi,

I am on bench for the last one and half months. My employer is forcing me to sign a leave notice, saying that's the only way he can keep my H1 active. If I do not, he is threatening to terminate my H1B and employment.

1) What will be the impact if I sign the leave notice ?
2) Can he possibly terminate my H1B in a day's notice if I do not want to sign it ?

Please suggest asap.