Defence Secretary Philip Hammond said the government is waiting for an announcement on the proposed BAE-EADS merger deal.
He told Reuters:
We are waiting for an announcement from the companies - the companies are dealing with it now.
They had a board meeting yesterday afternoon and evening. We are waiting to hear their announcement which I understand has to come today.
It is not for me to say who is doing what - it is the companies that now have the decision in their hands.
The UK's defence minister said the government is still waiting for an announcement from BAE and EADS on their proposed merger, adding the decision is "in the companies' hands", Reuters reported.
Defence companies BAE Systems and EADS are fighting to keep their proposed merger alive the UK, German and French governments wrangle over the deal before a crucial deadline today.
The government has drawn up a list of so-called "red line" issues detailing national security concerns of the proposed deal between BAE Systems and EADS.
The deal would create the world's biggest aerospace company with a market value of more than £30 billion and 220,000 staff.
Experts have raised concerns over the political hurdles the mega-merger faces, given the sensitive nature of national security work handled by the two firms and with approval required from a number of governments worldwide.
The British Government has a so-called golden share in BAE that allows it to veto deals that are seen to put the public interest at risk and has already said it will seek to ensure UK interests are "properly protected".
The Ministry of Defence (MoD) has told BAE Systems and proposed merger partner EADS they must provide safeguards over Britain's Trident nuclear weapons programme before the multi-billion-pound tie-up can go ahead, it was reported today.
Guarantees over Trident nuclear submarines - which are built by BAE at its yard in Barrow-in-Furness, Cumbria - are the top priority for the MoD and Department for Business, according to the Sunday Times.