Afghan President Hamid Karzai threatened Sunday for the first time to send troops into Pakistan to kill Taliban fighters if they pursued cross-border attacks.

Karzai said at a news conference that Afghanistan has the right to self-defense, and because guerrillas from Pakistan “come and kill Afghan and kill coalition troops, it exactly gives us the right to do the same.”

Analysts said they doubt military action by Afghanistan is imminent, but Pakistan’s prime minister said the threat “will not be taken well.”

Pakistan has warned it will not tolerate any violations of its borders.

Prime Minister Yousuf Raza Gilani said Pakistan did not interfere with other countries and would not allow any interference in its affairs.

His warning came after Afghan President Hamid Karzai threatened to send troops over the border into Pakistan to confront militants based there.

He said his nation had the right to retaliate in “self-defence” when militants crossed over from Pakistan.

Now the US has a double problem to be concerned with–if the attack comes will Pakistan remain in the US fold?