Labour says it will repeal parts of proposed telecommunications legislation if elected this November.

Labour's communications spokesperson Clare Curran said the planned the law would kill competition and harm consumers.

"Labour believes the (law) is deeply flawed and allows anti-competitive behaviour to the detriment of consumers. It blocks the influence of an independent regulator, and would result in steeper prices for New Zealanders," Curran said.

The Telecommunications (TSO, Broadband, and Other Matters) Amendment Bill paves the way for the Government's ultrafast broadband scheme, due to be rolled out to 75 per cent of New Zealand over the next decade.

It has come under fire from telcos and industry lobby groups because it would remove the Commerce Commission's ability to regulate prices of broadband until the end of 2019.

Communications Minister Steven Joyce has argued this is necessary to reassure the Government's private partner in the scheme they will get a certain return on their investment.

However, Curran said Labour opposed the forbearance period and would repeal this part of the law if it came to power.

Labour also had issues with sections of the law that allow Telecom to separate in two.

Telecom proposed to split its network arm Chorus from its retail branches as part of its bid for broadband contracts.

"Steven Joyce's new law delivers a sweetheart deal to Telecom which allows them to gouge profit at the expense of New Zealanders," Curran said.

"Providing a regulatory subsidy to the powerful incumbent is likely to halt investment from other parties not awarded the main contract. The focus should be to lift the industry as a whole. Labour supports the need to improve New Zealand's telecommunications infrastructure to encourage productivity, innovation and export led growth, she said.

Telecom is in the running to win the right to build the lion's share of the ultra-fast scheme and an announcement is due in the next fortnight.

Curran also struck out at Crown Fibre Holdings, the state-owned company responsible for handling the Government's $1.35 billion investment in fibre.

"(Crown Fibre Holdings) will act as both an investor and a quasi-regulator of the new fibre network. This creates a serious conflict of interest as Crown Fibre Holdings will be regulating its own investment.

"(It) lacks the independence and specialist skills to undertake such a task," she said.

The law is due to come back to Parliament from the select committee process on Monday.