Shadow foreign secretary Emily Thornberry has put herself at odds with her own party's policy on renewing the UK's nuclear deterrent, telling Sky News it was not "a top priority for me".
The Labour frontbencher refused to be drawn over whether she agreed with the party's official stance on the Trident missile system, insisting she was "not getting involved in any more fights about this".
But appearing on Sophy Ridge on Sunday, Mr Thornberry indicated her coolness, saying that: "Party policy is party policy."
She argued the biggest threat posed by Russia in the 21st century came from cyberattacks and warned against taking "our eye off the main game".
The Kremlin has rejected claims made by the UK Government earlier this year that it was "weaponising misinformation" in a sustained campaign of destabilisation against the West.
Labour was recently forced to restate its backing for the retention of Trident after Jeremy Corbyn, a lifelong opponent of nuclear weapons, appeared to throw its commitment into doubt.
The Conservatives seized on the confusion to claim Labour was in "chaos" and could not be trusted with the nation's defences.
Asked for her view on the nuclear deterrent, Ms Thornberry, a close ally of Mr Corbyn, said: "I think that the party has decided that we continue to renew Trident and the decision has been made, and generally the public seems to be in favour of us having a nuclear deterrent."
When pressed on her own personal opinion, Ms Thornberry said: "I think that we need to look at 21st century threats and I don't think that Trident is a top priority for me.
"I think that the biggest threat from Russia is things like cyberattacks.
"The cyber capability of Russia is, in terms of 21st century threats, a more immediate problem for us and the way in which they try to undermine democracy in the West."
Refusing to be drawn when asked if she disagreed with Labour policy, she said: "I am not getting involved in any more fights about this.
"Party policy is party policy. My view is that we should not take our eye off the main game, which is that the real threat from Russia is actually much more modern, much more subtle, much more nuanced and real now."