Approximately 13,000 military personnel from Estonia and allied countries are conducting a large-scale mobilisation exercise in locations throughout Estonia.

Code-named Siil / Steadfast Javelin, the exercise features more than 7,000 reserve forces, as well as over 600 soldiers from Belgium, Germany, Latvia, Poland, the Netherlands, as well as the UK and the US.

Involving armoured personnel carriers, artillery units, air defence systems, combat engineering and transport and support vehicles, the exercise aims to test the full staging of the permanent readiness soldiers and additional staging of rapid response reserve units.

The war games primarily focus on training the Estonian infantry brigade in ground operations, but will also involve air operations.

Estonian Defence Forces commander lieutenant general Riho Terras said: "This demonstrates the will Estonia’s reserve soldiers have to defend their own country, but also serves as an example how the society supports the reserve-based system."

"This demonstrates the will Estonia’s reserve soldiers have to defend their own country."

During the exercise, the participants will learn to receive mobilised personnel, while the First Infantry Brigade will exercise its operational capabilities as well as tactical and operational command.

The drill is also supported by the US M1A2 Abrams main battle tanks, Polish Su-22 attack aircraft, four UK Royal Air Force Eurofighter Typhoons, which are currently participating in the Nato Baltic Air Policing mission, as well as additional Hawks and US A-10 attack aircraft.

The Organisation for Security and Co-operation in Europe (OSCE) has sent observers to the exercise, which is claimed to be the biggest exercise in the Baltic Sea region this year and is scheduled to conclude on 15 May.

OSCE delegation includes 27 observers from the US, Austria, Georgia, the Netherlands, Italy, Norway, Poland, Portugal, Sweden, Romania, Germany, Finland, Switzerland, the Czech Republic, Hungary, Belarus and Russia.

Image: Exercise Siil / Steadfast Javelin focuses on training the Estonian infantry brigade in ground operations. Photo: courtesy of Estonian Defence Forces.