The union finance ministry is mulling a proposal to make Large Taxpayer Units (LTUs) compulsory for companies paying annual advance tax of more than Rs 10 crore, a senior official from the ministry said.

The official said that the move was part of the government's efforts to boost and streamline tax collection.

An LTU is a single window clearance for all matters relating to income tax, corporate tax and service tax and central excise. To look into the different aspects of LTU, the ministry has set up a four-member committee.

Revealing the development, the official said, "The committee is also examining whether to make it mandatory for companies who are paying advance tax more than Rs 10 crore in a fiscal year or service taxes more Rs 5 crore to register under LTU."

In case the government makes the LTUs mandatory, it may also review the thresholds for companies to avail the facility. Currently, those paying advance taxes of more than Rs 10 crore and service tax or excise of more than Rs 5 crore are eligible to register with LTUs.

Currently, it is not mandatory for large tax payers to register with LTUs.

The first LTU came into existence at Bangalore in 2006. Later, the government set up more LTUs at Chennai, Mumbai and Delhi.