LONDON, May 13 (Xinhua) -- Northern Ireland's Democratic Unionist Party (DUP) lived up to its threat and blocked the restoration of the power-sharing government.

In the Northern Ireland Assembly (Stormont), the DUP's politicians abstained in a vote on the appointment of a speaker, forcing the assembly's collapse. They ignored pleas by other elected members to allow the assembly and its cabinet of ministers to function.

Unless the DUP changes its mind, it could take up to six months before fresh elections would be held. In the meantime, there will be no functioning executive cabinet or assembly.

In last week's elections, the pro-Republican Sinn Fein party won majority support and the right to choose, for the first time ever, the administration's first minister. The vote left the previous majority-holder in the assembly, the DUP, with the right to name a deputy first minister.

Under the rules, the assembly and its executive cabinet cannot function unless a speaker, a first minister and a deputy first minister are all in place.

The DUP vehemently opposes the Northern Ireland Protocol, the trade solution agreed by London and the European Union (EU) to prevent a hard border between Northern Ireland and the neighboring Republic of Ireland. Under the deal, an Irish Sea border was created between the British mainland and Northern Ireland, meaning goods transported to and from Northern Ireland are subjected to border controls.

It has led to threats by the British government to tear up the protocol, a prospect hotly opposed by the EU. The focus now switches to UK Foreign Secretary Liz Truss, who needs to solve the protocol dispute with EU officials in Brussels.

In Friday's debate, the DUP's Gordon Lyons said: "We will not be going into an executive until we deal with the instability of the protocol and with the long shadow it is casting."

In a statement after the vote, Paul Murnaghan, president of the Northern Ireland Chamber of Commerce and Industry, described the decision as a blow to business and investor confidence.

He said: "At a time when our elected representatives should be getting straight to work to tackle a myriad of very significant challenges, we remain in limbo.

"We call on all political representatives to stop allowing division to hold back progress and form a stable, fully functioning assembly and executive without delay."