London — Despite severe blows against civilian and guerrilla concentrations in several parts of Afghanistan recently, the Soviet Union appears no closer to controlling the country now than it was in the early stages of the occupation over two years ago.
But British and other Western analysts are forecasting a vigorous intensification of anti-resistance operations in coming months.
''The Soviets have already begun to prosecute the war in a more energetic and ruthless manner involving both aerial attacks and military sweeps using ground forces,'' noted one London-based observer. ''This is likely to increase considerably in the spring and early summer.''
In the past three months, diplomatic, intelligence, and other sources have reported major communist incursions against guerrilla forces notably in the Herat, Kandahar, and Kabul regions. Although reports are often sketchy or contradictory, and difficult to verify, the guerrillas are believed to have suffered unprecedented casualties including the loss of several important local leaders. As many as 600 mujahideen may been killed or captured in sweeps in the Gulbahar region north of Kabul in late January and early February.
Although the resistance has certainly suffered setbacks, guerrilla activity continues with often poignant efficacy.
French sources maintain that resistance, particularly in the northern provinces, has been just as violent and frequent as during the summer months.
Convoys, military bases, and government buildings are still being attacked with regularity. Assassinations, kidnappings, and bombings are reportedly on the increase in the towns, notably Kabul.
In Mazar-i-Sharif, resistance operations have been so prevalent that the families of Soviet advisers were recently evacuated. One just returned French doctor, Jean-Louis Herrmann, who clandestinely spent 10 weeks in Loghar, said the mujahideen attacked the Kabul-Gardez highway almost daily.
During the bitterly cold winter months, some areas have witnessed what some observers consider to be a deceptive lull in fighting. Last year, many mujahideen found themselves too vulnerable to helicopter attacks in flat, snow-bound regions offering little or no cover. As a result, they have been lying low and are expected to emerge once the sparse spring vegetation provides some protection.
French and other sources believe that Soviet attempts to export 5 billion cubic meters of Afghan natural gas to its Central Asia republics by the end of 1981 has been frustrated by resistance attacks and sabotage. According to government figures, only 1.17 billion cubic meters were pumped across the border--slightly more than in 1980 but far less than in previous years.
Analysts regard Afghanistan's considerable natural gas reserves and its mineral and oil potentials as major factors behind Moscow's invasion of the primarily desert country in December 1979. Apart from serving to replenish gradually exhausted gas reserves in the Caspian Sea region, one military specialist says, ''Soviet exploitation of Afghanistan's natural gas is in fact fully paying for Moscow's costly military occupation.''
Although Moscow and Kabul agreed to a 13 percent price rise in a new gas export deal last January, it is still being sold at $100.34 per 1,000 cubic meters--substantially less than the $180 rate at which the Russians sell their gas to Western Europe.
Although the Russians recently increased their forces by an estimated 5,000, the roughly 90,000 troops is still far below the 400,000 considered necessary to control the country.
''For the moment, the Russians do not seem interested in expanding the war and prefer to stick to a long-term strategy of economic and political absorption ,'' said one observer. ''They have, however, begun to learn from the guerrillas and are changing their tactics accordingly.''
Although the Kabul regime has managed to boost slightly its armed forces to possibly 30,000 through press-ganging conscripts or by offering monetary incentives, the Soviets regard the Afghans as unreliable. Defections still run high and the Russians are known to be concerned about the growing number of trained recruits who have gone over to the resistance, often with their weapons.
As a result, there are indications that the Soviets have been sending more of their own men into direct combat.
Operating from heavily defended bases, the Russians have been hitting harder at the guerrillas, using ''cordon and thumb'' tactics - militarily cordoning off hot spots and then moving in--as a major tactic.
But Western analysts say this is not always effective. Moving in small groups , the guerrillas can easily slip away once they realize they are being encircled.
The French doctor and resistance sources have reported a rise in heavy Soviet aerial bombardments, the use of antipersonnel mines, and raids against towns and villages suspected of aiding the guerrillas.
Faced with the dilemma of trying to quash a popular uprising while also seeking to encourage support for the regime, the communists have adopted a policy of divide and rule. They are promising greater cultural and political autonomy among ethnic, regional, and tribal groups traditionally hostile to central authority. This has had only limited success.
Western analysts believe Soviet casualties are low compared to the US experience in Vietnam. Between 3,000 to 8,000 have been killed since the invasion, according to various sources. The resistance claims the figures are much higher. A communique issued last December by the Islamic (guerrilla) alliance in Peshawar, Pakistan, claimed that 9,000 Soviet and 4,500 Afghan soldiers were killed in 1981, while some 1,000 mujahideen and 20,000 civilians were killed during the same period.