By Tetsushi Kajimoto

NIIGATA (Reuters) -Japan will unveil a plan on Thursday to mobilise $1 billion to help countries surrounding Ukraine accept refugees from the war-torn country, Finance Minister Shunichi Suzuki said on Thursday.

The funding would be provided via the state-owned Japan Bank for International Cooperation (JBIC), which typically offers assistance in the form of lending, guarantees and equity investment, based on financing needs for each project.

The new funding also will be used to facilitate investment by Japanese firms in those countries, Suzuki told reporters as he arrived Niigata, north of Tokyo, to chair a three-day meeting of financial leaders from the Group of Seven (G7) advanced nations that kicked off on Thursday.

"We want to accelerate international cooperation needed to overcome difficulties the global economy faces," Suzuki said.

On Ukraine, the G7 will confirm financial support pledged so far and the effect of IMF support programmes, while boosting coordination among multilateral development banks and backing surrounding countries, Suzuki said.

The G7 will also debate how to prevent Russia from circumventing sanctions imposed after its invasion of Ukraine.

Suzuki made no mention of additional sanctions against Russia or further G7 financial support for Ukraine for the time being, signalling the financial leaders may take a wait-to-see stance to gauge the effects of earlier measures.

The G7 is comprised of Britain, Canada, France, Germany, Japan, Italy and the United States.

Last year, JBIC signed a memorandum of understanding (MOU) with Poland’s Bank Gospodarstwa Krajowego for mutual cooperation on energy security and climate change in Poland and elsewhere, including countries neighbouring Ukraine.

In March, JBIC signed an MOU with Romania's Ministry of Finance and Romania EximBank to strengthen cooperation on similar issues.

(Reporting by Tetsushi Kajimoto; Editing by Kim Coghill)