Monrovia - Liberian President Ellen Johnson Sirleaf said on Thursday she was working with Ivory Coast leader Alassane Ouattara to deal with deadly border attacks in his country.
She also denied there was tension between the two nations after Ivory Coast charged that the attackers who killed 18 people, including seven UN peacekeepers in western Ivory Coast last week, came from Liberia.
"I am not only concerned but I was also very involved in the national security meeting with my cabinet," Sirleaf told journalists.
"I was in personal touch with President Ouattara of Ivory Coast and the two countries are working together to be able to solve this problem."
Sirleaf said she would get a full report from her defence minister during a national security meeting on Thursday.
Last week Friday, at least 80 guerillas staged a deadly ambush on a UN peacekeeping patrol in Ivory Coast but the attackers have not yet been identified.
Seven peacekeepers from Niger, one Ivory Coast soldier and 10 civilians were killed in the attack last Friday which led to the closure of the border with Liberia.
Another four civilians were killed early this week in a fresh attack, the UN said on Wednesday.
The attacks came after a Human Rights Watch report said fighters loyal to ousted Ivorian leader Laurent Gbagbo were staging the attacks from Liberia.
The group said at least 40 people were killed in those raids since July 2011.
"There is absolutely no bad relationship between Liberia and Ivory Coast, we are best of friends. What we will do, will be done jointly by the two countries in the interest of our two people," said Sirleaf.
The instability along the border has been a concern ever since the end of Ivory Coast's conflict, which left 3 000 dead as Gbagbo refused to stand down after losing an election. He was captured in April last year.
Liberia has reported several "worrisome" seizures of weapons along the border, and in January said it arrested about 70 people "training and recruiting fighters to go against the government of Ivory Coast".