Coalition backbenchers joined Minchin, a long time rival of party leader Malcom Turnbull, and crossed-the-floor and walked out of one of the final senate meetings this year as the party relinquished its to safeguard the AUD$2.4 billion (US$1.55 billion) Communications Fund and instead pour it into the government's $26 billion Infrastructure Australia initiative.

Legislation drafted by the then Howard government to protect the fund was bypassed by a senate majority to appropriate the cash to stimulate investment in the economy. The backflip decision occurred after the party had voted to preserve the fund in the lower house and first senate round.

Attempts by the government to use the fund for its $4.7 billion National Broadband Network (NBN) were previously by the legislation which passed late last year . The bill was designed to restrict the now Labor government to spending only the interest earned from the Communication Fund's investments -- up to $400 million every three years.

A spokesperson for Minchin's office said the funds may be used to fund the government's NBN.

"Who knows what will happen to these funds that were an important revenue for regional Australian telecommunications," the spokesperson said.