The Minister for European Affairs says Britain must make clear it is not going to request rolling extensions to the Brexit deadline.
Helen McEntee said the Government would look favourably on a request to avoid a no-deal situation.
A bill seeking a further extension until 31st January 2020 is set to make it through all stages in the British parliament over the coming days.
However, Minister McEntee said Britain needs to make clear what kind of relationship it wants with the EU.
She said Britain has not developed a clear policy on Europe since the last extension was granted.
Speaking on Newstalk Breakfast, she observed: "I think what we would need to be clear about is that this is not something that would continue on an almost three-monthly basis.
"We've had an extension now since last April. Unfortunately, since that last extension I am no clearer on what kind of relationship the UK wants, how they would leave, and would that would look like into the future."
The bill to prevent no-deal is set to pass through all stages in the House of Lords by 5pm today, clearing the way for it to become law next week.
Yesterday, Boris Johnson said he'd "rather be dead in a ditch" than ask for another Brexit extension.
Jeremy Corbyn is due to hold a conference call with other opposition parties this morning in a bid to agree on a strategy to avoid no-deal.
They'll also discuss Mr Johnson's push for a general election, which is due to come before parliament again on Monday.
While Labour and other opposition parties have said they want an election, they've said it can only happen once a Brexit delay becomes law.
Mr Johnson has called for the election to be held in mid-October, ahead of the current Brexit deadline of 31st October.
Meanwhile, the British High Court may issue a ruling this morning on whether Boris Johnson's decision to suspend parliament is lawful or not.
The prorogation is due to come into effect from next week until mid-October.
While Mr Johnson has insisted it's a routine suspension, opponents have claimed it was a bid to limit efforts to stop a no-deal exit.
The High Court bid to block the move was initiated by campaigner Gina Miller, who was later joined by former prime minister John Major and deputy Labour leader Tom Watson.