The federal treasurer shot down questions of whether Australia could have done more to stop the Solomons moving away from Canberra towards Beijing.
"No. Because we've got a full court press with respect to our Pacific friends ... we provide about two-thirds of developmental assistance," he told Seven's Weekend Sunrise on Saturday.
Labor has jumped on the new revelations of the new pact, with frontbencher Tanya Plibersek saying the Solomons had expected more from Australia on climate change.
"We need to treat our neighbour with respect," she told ABC News.
The opposition education spokeswoman said climate change was a national security concern of the Solomons, with rising sea levels threatening the Pacific nation.
Meanwhile, Mr Frydenberg was waved off concerns about his placing on the ballot in his seat of Kooyong at the upcoming election, with the treasurer seventh on the 11-candidate ballot while his high-profile independent opponent Allegra Spender took pole position.
"There's the luck of the draw when it comes to the ballot, you just accept it and you move on," Mr Frydenberg said.
Elsewhere, Anthony Albanese is confident he will hit the ground running when he emerges from COVID-19 isolation next week, just in time for Labor's campaign launch.
The opposition's campaign has been dealt a major blow after Mr Albanese tested positive for the virus, with Labor frontbenchers stepping in for the next few days.
Labor is expected to campaign in NSW on Saturday during the second day of the opposition leader's isolation period.
Mr Albanese said the timing was unfortunate, but he was ready to get back on the campaign trail as soon as possible.
"This is a long campaign, and if I was going to get COVID, it is better to have got it now than in the last three weeks of the campaign," Mr Albanese said.
He will isolation at his Sydney home, before Labor's campaign launch in Perth on May 1.
Prime Minister Scott Morrison will spend day 13 of the campaign in marginal seats on the NSW Central Coast.
He spent much of Friday defending the government's response to the Solomon Islands signing a security pact with China.
Mr Albanese said he would look to strengthen relationships with neighbouring Pacific nations, should Labor win the election.
The Australian Electoral Commission on Friday finalised the ballot draw for all 151 lower house seats and eight Senate races ahead of the May 21 poll.
However, the commission referred former WA senator Rod Culleton to federal police for potentially making a false declaration on his nomination form.
Mr Culleton, who intends to represent the Great Australia Party, declared in his nomination he was not an undischarged bankrupt or insolvent.
The commission said it noted Mr Culleton was listed as an undischarged bankrupt on the National Personal Insolvency Index.
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