The threat of tariffs should be not used to pressure Thailand to start talks with Cambodia and halt renewed border fighting says Thai foreign minister Sihasak Phuangketkeow, underlining that it was up to its neighbour to de-escalate the conflict.br br Sihasak said on Tuesday (Dec 9) the current situation with Cambodia was not conducive for third-party mediation, insisting that Phnom Penh would have to show sincerity and make the first move.