The government must allow EU scientists and researchers already working in the UK to stay in the country, the Science and Technology Committee has urged.
With the nature of the UK's exit from the EU still unknown, the Parliamentary group warned that unsureness caused by Brexit is a threat to the UK's science sector.
Chair Stephen Metcalfe MP said: "Uncertainty over Brexit threatens to undermine some of the UK's ongoing international scientific collaborations. Telling EU scientists and researchers already working in the UK that they are allowed to stay is one way the Government could reduce that uncertainty right away."
He told Sky News: "Our committee is concerned that by not providing reassurances to EU nationals, that they won't come here and conduct their research in the UK. And we want to provide that reassurance early.
"I don't think it undermines the government's future negotiating position but it would provide the science community with the reassurance they need."
Ian Robinson, partner at immigration law firm, Fragomen LLP, agreed with the committee, saying EU citizens in the UK "need and deserve" to know they can remain in the UK post-Brexit.
"People aren't bargaining chips and it isn't fair to just string them along," said Robinson. "That is even before we get to the risk to science as a sector, indeed the risk to every sector, of talented people leaving the UK."
Trade secretary Liam Fox told the Conservative Party conference in October that the ongoing uncertain status of EU citizens living in the UK is "one of our main cards".
The committee added that science and research needs do not appear to be central to the Department for Exiting the European Union's (DExEU) plans, calling on it to hire a chief scientific advisor as soon as possible.
"The concerns and needs of our world-class research establishments and scientists working in the UK must be heard at the negotiating table," added Metcalfe.
He pointed to key aims, including securing access to EU science funding projects like Horizon 2020, ongoing collaboration of the UK science community with international colleagues, and ongoing access to EU research facilities.
DExEU referred IT Pro to the Department for Business, Energy, and Industrial Strategy, who provided a statement from Universities and Science Minister Jo Johnson, who said he will consider the committee's recommendations carefully.
He said: "The UK is a world leader in science and research, it's fundamental to our prosperity, security and wellbeing.
"We intend to secure the best possible outcome for our research base as we exit the European Union. The excellence of our research and the attractiveness of the UK as a place to do it are fundamental to our continued success.
"Our international relationships make us a global centre of excellence. I'm pleased that the report welcomed our August announcement that UK applicants should continue to bid for competitive EU research funding, such as Horizon 2020, while we remain a member of the EU.
This story was originally published at 11.13am on 18 November, and was updated at 12.16pm with comment from the government.
