The US apparently wants to create a new clause in the SMA in order to get Seoul to cover expenses related to the allies' combined military exercises and support for USFK troops' families.

Seoul insists that the negotiations should proceed within the SMA framework, which requires it to pay partial costs for Korean employees in USFK installations, construction of some military facilities and logistical support.

Some observers have raised the idea that Seoul could offer ways that it can contribute to US-led efforts in safeguarding the shipping lanes in the Strait of Hormuz, off Iran, as a possible bargaining chip in its SMA negotiations.

The presidential office Cheong Wa Dae said last week that its security officials reviewed what options Seoul has for contributing to the efforts for the maritime security in the region.

Some others say Seoul could also use its plan to carry out the decontamination work in four returned US military bases here as a counteroffer to the US' call for the drastic hike in the defense cost-sharing. The clean-up process is estimated to cost about 110 billion won ($92 million). (Yonhap)