The Biden administration is under pressure to increase lethal aid to Ukraine once again, particularly in the way of rocket firepower, in an effort to push toward ending the Russian war.

As Russia is ramping up intensity in the battle for the Donbas region, Ukraine is making calls for more air defense missiles, defense systems, and other military equipment, and defense officials and experts are adding the pressure on President Joe Biden to acquiesce to the demands in an effort to stem, if not end, the Russian offensive.

The Biden administration added $7.3 billion in lethal aid to Ukraine this week after $400 million the previous week included four of the High Mobility Artillery Rocket System (HIMARS), The Hill reported.

The HIMARS are mobile truck-mounted systems that can send satellite-guided missiles at ranges of more than 40 miles. Ukraine President Volodymyr Zelenskyy told Newsmax in an exclusive interview in Kyiv in late May that he seeks HIMARS with ranges from 120 to 140 kilometers.

Thus far, there have been 12 HIMARS pledged to Ukraine since June, and they have been used to strike 20 Russian ammunition depots in the past few weeks, The Hill reported.

"HIMARS have already made a HUUUGE difference on the battlefield," Ukraine Defense Minister Oleksii Reznikov tweeted last week. "More of them as well as US ammo and equipment will increase our strength and help to demilitarize the terrorist state. I highly appreciate the efforts of the @POTUS & @SecDef to support Ukraine's struggle for freedom!"

Ukraine has four HIMARS already in place, with four more to come, but it has noted it needs up to 300 multiple-rocket launchers to fight the Russians, according to the report.

"I think the administration in fact, I know that they don't want to send equipment over before the Ukrainians are ready to maintain and operate," the Center for Strategic and International Studies' Mark Cancian told The Hill.

"I think also the administration is concerned that at some point … someone's going take a picture of a field full of junked equipment that the Ukrainians couldn't maintain anymore. I think that is what's causing the administration to pace what it provides out."

Former Supreme NATO Commander retired Gen. Wesley Clark is projecting Russian troop reserves could be ready to make a move to break the stalemate in the Donbas.

"With Russian reserves being formed up, some 20 to 40 battalion groups have been held back, there could be a strategic breakthrough," Clark told CNN last week, adding "that breakthrough" might "be the key to getting the Ukrainian army defeated in Donbas."

Despite hopes for an end to the war on the horizon, multiple people expect fighting to last "years," including NATO Secretary-General Jens Stoltenberg.

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