Britain's North Sea oil industry faces increased uncertainties following the "leave" result in the country's EU referendum, according to rating agency Standard & Poor's.
Oil companies are likely to take an indirect economic hit as the outcome weakens the "predictability, stability and effectiveness of UK policymaking", the agency said.
The vote result is likely to affect the UK's economy, GDP growth, and fiscal and external balances.
The likelihood of a second independence vote in Scotland, which voted overwhelmingly to stay in the EU in the June 23 vote, is likely to compound the uncertainty.
S&P has already reacted to the referendum outcome by downgrading the UK's sovereign rating on June 27.
The agency said it believed the direct rating consequences for companies operating in the UK North Sea were limited.
But it added: "That said, the increased short-term political, fiscal, or financing uncertainties are unlikely to support any reversals in the declines in investment and exploration since 2014, spurred by falling oil prices.
"What's more, even if North Sea investment were to pick up following the two or so years of negotiating the terms of a 'Brexit', the impact of a lack of spending in 2016 and 2017 could potentially have disproportionate consequences."