The regional development minister has said 'Welcome to Northern Ireland' signs that have been put up in border areas are purely for information.
Sinn Fein has said the signs are antagonising nationalists and are a waste of money.
In County Fermanagh a number of the signs are already down.
The minister Danny Kennedy said there was no "no great constitutional drama" about the signs and some people were "getting carried away".
"These signs are entirely for information purposes," he said.
"They're welcoming visitors, particularly the many tourists who cross the border, to Northern Ireland and to remind them that speeds are measured in miles per hour, rather than the European measure of kilometres."
However, Sinn Fein's Phil Flanagan said the signs had been put up "for political reasons".
"The roads minister has put them up to mark out territory," he said.
"People in the border area who have to face the challenges of living in a border area are very antagonised by this and they can clearly see the reason behinds this.
"People are very angry and people want the signs down."
The Northern Ireland Tourist Board said the responsibility for all road signs lay with the Roads Service.
"Roads Service has agreed that Welcome to Northern Ireland signs should be considered as part of each border council's annual tourism audit," it said.
A Roads Service spokesman said: "Signage is placed at strategic border crossing points to remind drivers entering Northern Ireland that speed limits are displayed in miles per hour.
"Roads Service is supplementing the existing signage with 'Welcome to Northern Ireland' signs indicating the change of jurisdiction.
"The programme of work is ongoing and five out of a total of eight signs have been placed at an approximate total cost of £950."