Alison Hume raised the future of the laboratory in the Commons on Thursday, asking ministers to reaffirm support for Britain's bid to host the XLZD experiment.
Science minister Chris McDonald said the laboratory's development was funded until 2027-28. He added that a successful UK bid would require additional money beyond existing budgets.
The Boulby facility, based in a working mine, is seeking to host research designed to detect dark matter. Supporters say landing the experiment would reinforce Britain's position in fundamental physics and bring investment to North Yorkshire.
McDonald also explained that increased capacity had raised the laboratory's rental costs, with about £500,000 of its £1 million operating budget carried into a wider £4 million budget.
The exchange provides certainty for development work but not a guarantee that the UK will win the international competition or that the later capital and operating costs have been approved.
Hume, Labour MP for Scarborough and Whitby, has placed the funding gap on the record before the host decision, giving ministers an early warning that success would require a further commitment.
