The North Atlantic Treaty Organization (NATO) allies have boosted support to Ukraine with military equipment, financial assistance and humanitarian aid, NATO Secretary General Jens Stoltenberg said Monday via Twitter.

"NATO Allies are stepping up support with air-defence missiles, anti-tank weapons, as well as humanitarian and financial aid," Stoltenberg tweeted.

NATO said in a press release on Sunday that Ukraine has received "critical weapons," including Javelin missiles and anti-aircraft missiles.

"Millions of euros" worth of financial assistance and humanitarian aid have also been sent to the Ukrainian forces, NATO added.

Russia launched a military operation against Ukraine on Feb. 24. After a seesaw struggle between the two sides, a ray of hope emerged as the Ukrainian and Russian delegations arrived at the Ukrainian-Belarusian border for talks on Monday.