A British research institute says Russia has lost nearly 3,000 battle tanks during its invasion of Ukraine, but a stalemate in the fighting may continue.

The International Institute for Strategic Studies published its annual "The Military Balance" report on Tuesday. The document analyzes countries' military power and regional situations around the world.

The report says Russia has lost over 2,900 battle tanks since launching its full-scale war on Ukraine. It says the figure is as many as the military "had in active inventory at the outset of the operation."

But the institute says Moscow has been pulling older tanks out of storage. It sees that Russia "could potentially sustain around three more years of heavy losses and replenish tanks from stocks."

The report says Ukraine has also suffered heavy losses, although the country has broadly sustained its inventory size thanks to replacements from Western nations and by using less costly unmanned ships and other weapons. The document adds that a stalemate in the fighting may persist thorough this year.

The IISS notes that the global security environment is worsening due to the war between Israel and Hamas, China's military activities around Taiwan and other factors. It points out that governments need to reassess their defense plans.

The report says global defense spending in 2023 totaled a record 2.2 trillion dollars, up 9 percent in real terms from the previous year.

The United States had the largest defense budget with 905.5 billion dollars, followed by China with 219.5 billion dollars and Russia with 108.5 billion dollars. Japan's defense spending was the ninth largest at 49 billion dollars.