Newly appointed Culture Secretary Matt Hancock has accused unelected peers of voting to curb press freedom after they backed controversial regulation and the go-ahead to part two of the Leveson Inquiry.
The Cabinet minister said it would be a "hammer blow" to the local press and he would seek to overturn the changes in the elected House of Commons.
Mr Hancock's response was swift after the double defeat of the Government in the House of Lords.
Following a lengthy and impassioned debate, peers voted by 238 votes to 209, majority 29, for a further hearing into alleged data protection breaches by the media.
Supporters of the move argued it was needed amid claims of ongoing press abuses while opponents said it amounted to "harassment" of the media.
The upper chamber also backed by 211 votes to 200, majority 11, a controversial measure which would see newspapers not signed up to a state-supported regulator pay their own and their opponent's legal costs in relation to alleged data protection breaches, even if they were successful in court.
This was despite warnings the move was unlawful and was effectively "blackmail" of the media.
Soon after the votes, Mr Hancock tweeted: "House of Lords have just voted to restrict press freedoms. This vote will undermine high quality journalism, fail to resolve challenges the media face and is a hammer blow to local press. We support a free press and will seek to overturn these amendments in the Commons."
The challenges came during the report stage in the Lords of the Data Protection Bill, which will bring the European Union's general data protection regulation (GDPR) into domestic law, helping Britain prepare for Brexit because it will mean the systems are aligned when the UK leaves the bloc.
It also aims to make it simpler for people to control how companies use their personal details, with extra powers for the information watchdog to issue much larger fines.