A YouGov poll of 5,401 Britons on Friday found 27% think Johnson's Conservative government would be better at handling Britain's response to Russia's invasion of Ukraine than a Labour administration run by Starmer (20%).
Meanwhile, 27% said neither government would do a better job. A further 26% of respondents said they didn't know.
Nonetheless, the survey indicates a possible softening of attitiude towards the prime minister following a scandal-hit few months, with the Downing Street lockdown parties saga seeing Tory poll ratings plummet to 28% in January - having been at 49% two years prior.
For Labour, the poll may also indicate a continued hangover from Jeremy Corbyn's leadership between 2015 and 2020, during which the party's national security credentials were repeatedly brought into question.
Before the 2019 general election, which saw Corbyn lead Labour to its worst result since 1935, Sir Richard Dearlove, the former boss of MI6, even said Corbyn as a prime minister would be a “present danger to our country”.
Watch: Putin calls on neighbours not to sanction Russia
Johnson has been criticised for his own response to the Ukraine crisis surrounding Russian sanctions.
On Thursday, Labour MP Liam Byrne labelled Johnson a "poodle on roubles" over a failure to impose tougher UK sanctions on more than 20 oligarchs or associates of Vladimir Putin.
Meanwhile, Downing Street has said Johnson rejects calls for Putin to be assassinated.
It follows comments made by US senator Lindsey Graham, who urged Russians to kill their leader. Asked if the PM agreed, his spokesman said on Friday: “No, we stand with the Ukrainian people in demanding the immediate end to the Russian invasion.
“We’ve said before that Putin must be held [to] account in front of an international court for the horrific act he’s committed.”