Samajwadi Party chief Mulayam Singh Yadav has written to the Rajya Sabha Chairman informing him about expulsion of Ram Gopal Yadav, a member of the upper house, an official said.

Gurdeep Singh Sappal, who is the officer on special duty with Vice President Hamid Ansari, who is ex-officio the Rajya Sabha Chairman, said the letter was being examined.

"Chairman Rajya Sabha has received letter frm Sh. Mulayam S Yadav, intimating expulsion of Sh. Ramgopal Yadav from SP-will be duly examined," Sappal said in a tweet.

Mulayam Singh, in the letter, also urged the Rajya Sabha Chairman to shift Ram Gopal Yadav's seat to the back benches.

At present, Ram Gopal Yadav, as the leader of SP in Rajya Sabha before his expulsion, occupied a seat in the front row along with Bahujan Samaj Party chief Mayawati.