BAE Systems is set to takeover tank maker Alvis after rival bidder General Dynamics conceded defeat in the battle.
In a surprise move on Thursday, UK defence giant BAE upped its offer to £355m, outgunning a £309m bid tabled by General Dynamics.
In a statement to the London Stock Exchange, General Dynamics said it would not be revising its earlier bid.
BAE said that the deal was "to the benefit of future Ministry of Defence programmes and the UK armed forces".
On Thursday, Alvis's board - which had earlier supported the US firm's bid - said it would now be supporting the 320p a share bid from BAE Systems.
Earlier, government regulators had said they had no objections to the bid from General Dynamics, despite concerns being raised over the protection of classified UK data raised by the Ministry of Defence.
Alvis builds the British Army's Challenger 2 tanks and employs around 2,800 workers.
It has operations in the UK, Scandinavia and South Africa, and customers in more than 40 counties - after starting life in 1919 as a car manufacturer.
BAE Systems currently owns 28.7% of London-based Alvis.