UKIP Defence Spokesman Mike Hookem MEP has called on the Foreign Secretary to rule out British troops being sent to Libya as part of an EU battlegroup.
Mr Hammond is under fire after MPs on a trip to North Africa were told that 1000 British troops were to be deployed as part of a 6000 strong international force against Da'esh.
Mr Hookem, who sits on the European Parliament's Defence Committee, said the plans for an EU battlegroup in Libya were "openly discussed and part of a three stage strategy by the EU to deal with terrorism and people trafficking."
"I have heard from senior members of the EU's military teams including the EU Border Assistance Mission in Libya (EUBAM) about their strategy for dealing with terrorism and trafficking, of which the third stage is 'boots on the ground'.
"Back in February leaked documents revealed the EU's plan to expand 'Operation Sophia' in order to move 'EU military assets' into Libyan waters - stage 2 of their strategy.
"We know from internal EU briefings that we are already at stage one of these proposals and that stages two and three are established, but not yet approved.”
"In a recent meeting I attended with Lieutenant General Wolfgang Wosolsobe, Director General of the EU Military Staff, he told MEPs, 'The EU military operation against traffickers is about to enter its next phase,' adding he would be seeking a UN mandate for 'his forces' to intervene in Libyan territorial waters.
"Any move to put naval assets in Libyan waters, or ‘boots on the ground’ would require UN authorisation, especially as there is no unified government in Libya to authorise action of this type.
"Senior defence sources have told me that the while NATO’s high command has ‘little stomach’ for further western intervention in Libya, the EU high command is ‘pushing the issue of intervention in Libya forward’.
"For me this highlights how the European Commission has ulterior motives and would use its involvement in this complex, protracted and multifaceted conflict to bolster its push for the creation of a combined EU army, which we know some EP parliamentary groups wish to see in place by 2025.
"The fact is that any ground forces deployed in Libya could quickly find themselves fighting multiple enemies, on multiple fronts. We have already seen what a mess Western leaders made in Libyan through their intervention to topple Gaddafi with President Obama admitting it was his worst mistake.
"Both the Foreign Office and the Ministry of Defence, who are wholeheartedly against Brexit and would dearly love to keep this kind of information away from the British public, need to come clean."