The DUP leader says his party will not be nominating any ministers to the Northern Ireland Executive.
Jeffrey Donaldson has told Secretary of State Brandon Lewis that the DUP will not bring forward any nominations without "decisive action" on the Northern Ireland Protocol.
Speaking outside Erskine House in Belfast, he said the DUP wants to see "stable political institutions" and to be a part of the Executive.
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"We have had a meeting with the Secretary of State and we have made our position clear to him and it is the position that we have held before the election, throughout the election campaign and will continue to hold," he said.
"And that is, until we get decisive action taken by the UK government on the Protocol, we will not be nominating ministers to the Executive.
"We want to see stable political institutions, we want to be part of the Executive. We want to play our part and fulfil the mandate we have been given by the people of Northern Ireland.
"We are also clear given the damage and harmful impact the protocol continues to have on Northern Ireland, driving up the cost of living, harming our economy, impeding the ability of businesses to trade with our biggest market and fundamentally undermining political stability, undermining the principle of consensus politics.
"We need this to be resolved.
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"When we re-entered the Executive back at the beginning of 2020 we did so on the basis of a clear commitment by the UK Government under the New Decade, New Approach agreement to address and protect our ability to trade with the rest of the United Kingdom."
Meanwhile, SDLP leader Colum Eastwood said his party will not nominate another infrastructure minister to sit in a "zombie Executive".
A vacancy arose after Nichola Mallon lost her Assembly seat in North Belfast in the recent elections.
Mr Eastwood said it would be undemocratic for his party - which was returned with a reduced mandate - to be in the Executive.
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