NATO defense ministers were gathering in Brussels on Thursday, in a fresh show of resolve against Russia while hoping to prevent a series of festering trans-Atlantic disputes from undermining unity across the 29-nation military alliance.

The ministers are set to unveil a new plan to reinforce their presence in Europe in the event of any crisis with the deployment of 30 troop battalions, 30 squadrons of aircraft and 30 warships within 30 days.

Details of the plan, drawn up by the U.S. and to be in place by 2020, are sketchy.  

The ministers are also likely to announce a strengthening of maritime operations, particularly in the Mediterranean Sea, where Russian ships have been shadowing allied vessels.

"We are working very closely with our allies, having discussions to make sure that we actually play a really vital contribution to that force, but as yet we have not actually agreed as to exactly what those numbers are going to be," said UK Secretary of State for Defence, Gavin Williamson.

He added that the Royal Air Force (RAF) will be deployed to Estonia and Iceland next year.

The meeting is set to make official staffing levels of more than 1,200 personnel for new commands covering the Atlantic Ocean based in Norfolk, Virginia and another in Ulm, Germany handling logistics during any conflict on mainland Europe.   

The defense ministers' meeting comes just five weeks before a summit of NATO leaders, to be attended by U.S. President Donald Trump.