Stormont must ensure the full delivery of abortion services "without further delay", Secretary of State Brandon Lewis has said.
The UK government has taken further legislative steps in a bid to ensure the commissioning of fully-funded abortion services in Northern Ireland.
Abortion laws in the region were liberalised in 2019 following legislation passed through Westminster when Stormont's power-sharing government had collapsed.
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While individual health trusts currently offer services on an ad-hoc basis, the Department of Health has yet to centrally commission services due to political stalemate on the issue.
The DUP, which is opposed to abortion, has refused to agree to the issue being tabled on the agenda of the Executive.
Mr Lewis had given the administration a March 31 deadline to commission services, but the Executive is currently not functioning due to an impasse over Brexit's Northern Ireland Protocol.
The Northern Ireland secretary has now moved to introduce regulations at Westminster that remove the need for Stormont's Department of Health to seek approval from the wider Executive.
Mr Lewis has asked for a "clear and unambiguous commitment" from Health Minister Robin Swann, who remains in post in a caretaker capacity, to progress the matter without delay.
If the minister does not act, the regulations laid by Mr Lewis also empower him to commission the services himself.
In preparation for that scenario, Mr Lewis has established a team of medical experts within the Northern Ireland Office to work alongside the Department of Health and assess progress.
Mr Lewis said: "Women and girls of Northern Ireland must have access to safe, high-quality abortion services in Northern Ireland, as is their right.
"It is absolutely unacceptable that the Executive and Department of Health have failed women and girls, meaning that they cannot currently access the same basic abortion healthcare that is available to women and girls in the rest of the UK.
"That's why I am acting to remove any further barriers to delivering services.
"The Department of Health must drive forward the commissioning of abortion services without further delay to ensure that safe abortion becomes embedded into the health and social care system in Northern Ireland."
Grainne Teggart, campaigns manager for Amnesty International UK, said the move was "welcome and necessary".
"Once again action from Westminster is needed to ensure that abortion rights are realised here," she said.
"Commissioned services, accessible to all who need them, are long overdue. We need to see a swift end to our postcode lottery for provision."
DUP MP Carla Lockhart criticised the decision as "overreach" by the UK government into devolved matters.
She told BBC's Good Morning Ulster: "In 2019 Northern Ireland had some of the strongest protections for the unborn.
"Unfortunately the UK government, after a Labour MP introduced this to the House of Commons, moved to legislate for Northern Ireland.
"We warned against it at that stage, we voted against it, the DUP remains a pro-life party, we said it was an overreach and we said that it would impact the devolution settlement in Northern Ireland."
She added: "This is a devolved issue. This should be for the people of Northern Ireland to decide what services they want, if any, to provide."
In a statement Health Minister Robin Swann said: "The Secretary of State's written statement and new regulations will be given careful consideration by my department.
"I will be seeking further legal advice, including with regard to a Northern Ireland Minister of Health's legal responsibilities under the Norther Ireland Ministerial Code."
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