Vauxhall's brand and "committed workforce" are highly valued, Business Secretary Greg Clark has been told during crunch talks in Paris over the future of thousands of British production jobs.
The minister travelled to the French capital on Thursday to meet French industry minister Christophe Sirugue and board members of PSA Group, which is in talks to acquire General Motors' loss-making European operation.
The deal would include Vauxhall, which has plants at Ellesmere Port and Luton employing around 3,500 staff.
Mr Clark said: "I had constructive meetings in Paris with both my French counterpart, the industry minister, and executives of PSA Group, in which they explained the rationale behind this potential alliance.
"They stressed that they valued highly the enduring strength of the Vauxhall brand, underpinned by its committed workforce. While discussions are still ongoing, they made clear to me that in any deal these were strengths they would wish to build on.
"We agreed to remain in close contact during the period ahead."
This comes after GM said it would put Vauxhall in the "strongest possible position for the future" after attending talks with the Government and unions at Westminster on Thursday.
GM president Dan Ammann met Mr Clark and Unite general secretary Len McCluskey as concerns mount over Vauxhall's 35,000-strong UK workforce.
Mr McCluskey said he had received "no assurances at the moment" over Vauxhall's workforce, but believes "concrete proposals are imminent".
However, Mr Clark struck a more positive note, saying the GM talks had been "constructive" and he was reassured that the plants would not be "rationalised".
Unite is also seeking a meeting with PSA Group at the earliest opportunity to discuss the proposed deal which would see Vauxhall and Opel shift to the French government-backed automotive giant.
The tie-up would cause GM to exit the UK and Europe, while transforming PSA Group into Europe's second-largest car maker with a 16% share of the market.
Following the GM talks, Mr Clark said he "emphasised the importance and successful presence of Vauxhall in the UK and welcomed GM's recognition of the excellent and committed workforce" at Ellesmere Port and Luton.
"There is some way to go in discussions between GM and PSA, but I was reassured by GM's intention, communicated to me, to build on the success of these operations rather than rationalise them."
Vauxhall is a major employer in the UK, with around 35,000 staff, including 23,000 in its retail network, 300 at a customer contact centre in Luton and 7,000 in its supply chain alongside workers at its two factories.
Mr McCluskey said the UK Government should demand that it has a seat at the table whenever PSA Group and GM meet for talks with the French and German governments in the future.
Earlier this week, the union leader said Vauxhall's UK plants must be offered the same Government assurances as Nissan, adding: ''It does seem as if Brexit is a factor in this decision as GM does rely heavily on its links throughout the EU supply chain."
Nissan announced in October that it was investing in production of new Qashqai and X-Trail models at Sunderland after receiving Government assurances that EU withdrawal would not affect the plant's competitiveness.
Germany has already expressed concerns at the proposed takeover, with Chancellor Angela Merkel's cabinet discussing on Wednesday what impact the tie-up would have on the 19,000 German jobs at Opel.
PSA Group, which owns the Citroen and DS brands, formed an alliance with GM in 2012 in an attempt to make production more efficient by combining purchasing power and larger scale.
GM said last year that it had to raise UK car prices by 2.5% after the plunge in the value of the pound following the EU referendum result caused the British car industry to hit a ''speed bump''.
Announcing its full-year results last week, the Detroit-based firm behind Chevrolet and Cadillac said GM Europe had narrowed losses to 257 million US dollars (£206 million) in the year to the end of December, from a loss of 813 million US dollars (£651 million) the year before.
Former business secretary Sir Vince Cable warned that uncertainty over Britain's exit from the European Union would make negotiations more difficult.
He told BBC Radio Four's Today programme: "There is a new element of course which is uncertainty over Britain's participation in the single market and the customs union.
"Vauxhall are part of the integrated European operation, most of their exports go to the European single market, most of their components come from the European supply chain.
"If you are the new owners - Peugeot - you are going to be extremely worried about what will happen when Brexit occurs."