Foreign aid cuts by Australia are partly to blame for the controversial security deal between China and Solomon Islands, Shadow Treasurer Jim Chalmers says.
But he added that foreign aid funding makes up only part of Australia's relationship with Pacific neighbours.
"Foreign aid is an important part of the story, but it's not the whole story," he said.
"Our relationships with our Pacific Island friends are crucial, and they are broader than the aid relationship."
Labor continues to accuse Prime Minister Scott Morrison of bungling the relationship following the pact, which the US, Australia and New Zealand fear could lead to a Chinese naval base in the South Pacific.
It comes as the White House has promised to bring forward the re-establishment of a US embassy in Honiara and to provide the country with more medical aid in the days following the agreement.
Analysis from the Lowy Institute suggests Australia's aid spending in the Pacific increased 24 per cent between 2009 and 2019.
However, the same work found that funding to the Solomon Islands decreased 43 per cent to $US129 million ($178 million) in 2019 from a peak in 2011.
"It is a fact that the government has cut aid," Mr Chalmers said.
"And it is a common view across the national security establishment, that that has been detrimental to our interests in the Pacific."
He said Labor plans to detail their policy on the Pacific later in the campaign.
"Foreign aid is part of the story, but it's not the whole story. Climate change matters to our Pacific Island friends," he said.
"The way that we manage our defence investments matters to our Pacific Island friends, and so does our aid relationship."
More questions have been raised over when the government first became aware of the controversial agreement, with Nine Newspapers reporting that Australian intelligence agencies played a role in leaking the draft deal on social media.
Foreign Minister Marise Payne told Senate estimates earlier this month she only became aware of the draft agreement after it was leaked online.
Mr Morrison refused to answer questions from reporters on Saturday over his government's management of the issue.
Treasurer Josh Frydenberg said the Coalition always knew there was a risk the Solomon Islands would sign a security deal with China when questioned on the issue.
Mr Frydenberg said the Coalition had been heavily engaged with Solomon Islands.
Australia's Minister for the Pacific, Zed Seselja, travelled to Honiara to urge Solomon Islands Prime Minister Manasseh Sogavare not to sign the deal less than a week before it was signed.
"Well we've known that this was always a risk, we've known that there were discussions underway, we've known there was always a risk of such a partnership," Mr Frydenberg said.
Labor deputy's record on China scrutinised
Deputy Labor Leader Richard Marles has faced further attacks from the Coalition over his record on China.
Mr Marles said he showed Chinese diplomats the contents of a speech he was planning to give in Beijing in 2019 because he wanted to make sure the Chinese government was not surprised by what he was going to say.
He gave the speech at the Beijing Foreign Studies University and provided the Chinese embassy in Canberra a copy of his remarks before delivering them.
Mr Marles said he did not change his speech, adding that he criticised the Chinese government over its human rights record and treatment of the Uyghurs population during the address.
"I made a speech in China where I criticised China, and I wanted to make sure the Chinese government weren't at all surprised by the fact of what I was going to say," Mr Marles said.
Establishment of US embassy welcomed by both sides
Coalition frontbencher Simon Birmingham supported the deeper engagement from the United States after senior officials visited Honiara, including the Indo-Pacific coordinator of the National Security Council, Kurt Campbell.
"We welcome deeper engagement by all of our partners in the Pacific," he said.
"Australia has a comprehensive network of embassies and high commissions across Pacific Island nations."
Shadow Minister for Education Tanya Plibersek also welcomed the move to reopen a US embassy in the Solomon Islands.
"I think the fact that the US embassy has been closed in the Solomons for some time is perhaps something to be remedied now," she said.
"Australia is a Pacific nation. And the United States has very strong interests in the Pacific as well.
"We are always delighted — Australia is always delighted — when the United States pays more attention to our Pacific neighbourhood."