The foreign minister of the Marshall Islands has called for more U.S compensation over the legacy of massive U.S nuclear testing to enable the renewal of a strategic agreement governing bilateral relations.

Marshall Islanders are still plagued by health and environmental effects of 67 nuclear bomb tests from 1946 to 1958, which included Castle Bravo at Bikini Atoll in 1954 – the largest U.S bomb ever detonated.

Jack Ading told a U.S congressional hearing a memorandum of understanding covering terms to extend his country’s Compact of Free Association (COFA) with Washington was signed in January without proper domestic authorization and under pressure of a deadline for inclusion in Joe Biden’s budget.

“There are other issues that needed to included, and especially, additional funding for the nuclear-affected populations,” he told the Senate committee on energy and natural resources.

He said the MOU was non-binding and appealed to Congress to direct the Biden administration to continue negotiating.

The Marshall Islands is one of three Pacific island nations covered by COFAS, under which the U.S has responsibility for their defense and provides economic assistance, while gaining exclusive access to huge strategic swathes of the Pacific.

Renewing the deals, which is subject to congressional approval, has become a key part of U.S efforts to push back against China’s bid to expand its regional influence.

Under MOUs agreed this year, the U.S will commit a total of $7.1bn over 20 years to the three nations.

In May, the U.S said it had finalised terms with Micronesia and Palau and its chief negotiator Joe Yun said then he hoped to complete a deal with the Marshall Islands in coming weeks. The economic terms of its existing Cofa expire this year.

Last year, more than 100 arms-control, environmental and other activist groups urged the Biden administration to formally apologise to the Marshall Islands and provide fair compensation.

Yun told the hearing he was “puzzled” by the Marshall Islands’ position, given the MOU offered it US$2.3bn over 20 years and that the nuclear liability issue had been settled in the 1980s. He also said the MOU contained US$700m for a trust fund that could be used for nuclear-affected atolls.

“I have told my Marshalese colleagues: listen, there is no more money,” he said.

Yun said he believed there were domestic political issues at play in the Marshall Islands, with an election coming up in November and rumours of a no-confidence motion against David Kabua, the president, next week.

Ading denied this and said he was “saddened and disappointed” by the reference to his country’s internal affairs.