DUBLIN, June 7 (Xinhua) -- The temporary arrangements, or called "backstop", to avoid a hard border between Britain's Northern Ireland and Ireland after Brexit can not be time limited by a date, said Irish Prime Minister Leo Varadkar on Thursday.

The remarks were made by Varadkar shortly after the British government published its proposals on the "backstop" policy, in which it said that the temporary "backstop arrangements to prevent a hard border between Northern Ireland and Ireland should not continue beyond December 2021, according to local media RTE.

Varadkar told local media that the agreed protocol, or "backstop", will apply until there is an alternative in place between Britain and the European Union (EU) that prevents a hard border.

He said the "backstop" has to be all weather and applicable until if and whenever a new agreement emerges that ensures there is no harder border in Ireland.

Irish Deputy Prime Minister and Minister for Foreign Affairs Simon Coveney said in a statement following the publication of the British government's "backstop" proposals on Thursday that he will look forward to discussing Britain's written proposals, aimed at making progress in the Brexit negotiations, with the EU negotiating task force.

He said that "The Task Force will be assessing whether these proposals have the potential to help deliver the UK's repeated commitment to avoiding a hard border."

"The EU has been clear that the backstop is an essential element of the EU-UK withdrawal agreement and that negotiations can only progress as long as all commitments undertaken so far are respected in full," he said.

"Ireland and the Commission have both stressed that substantial progress on the backstop is needed before the June European Council. Based on the negotiations between the UK and the Commission Taskforce in the coming days and weeks, Michel Barnier (EU's Brexit chief negotiator) will make an assessment of progress, for consideration by the Taoiseach (Irish Prime Minister) and his counterparts at the European Council three weeks from now," he added.

Britain will withdraw from the EU in March 2019.