North Korea on Tuesday refused to rule out a pre-emptive attack, even amid signs it may be willing to return to the nuclear bargaining table. The North poured out anti-American rhetoric _ a tactic it has used in the past before entering negotiations _ by claiming that Washington's "hostile policies" led it to develop nuclear weapons as a deterrent and warning against any attack to dislodge its leadership. "The United States should be aware that the choice of a pre-emptive attack is not only theirs," the North's official news agency quoted the state-run newspaper Minju Joson as saying. "To stand against force with force is our unswerving method of response." The commentary came amid a flurry of contacts aimed at convincing the North to resume six-nation talks, suspended since the third round ended in June, on its nuclear program.