Thousands of protesting Indian farmers equipped with cranes and excavators were set on Wednesday to march to New Delhi, the capital, after talks with the government on guaranteed prices for their produce failed to break a deadlock.

The action, watched by security forces clad in riot gear, came after farmers’ groups rejected a government proposal this week for five-year contracts and guaranteed support prices for produce such as corn, cotton and pulses.

The farmers, mostly from the northern state of Punjab, have been demanding higher prices backed by law for their crops. They form an influential bloc of voters Prime Minister Narendra Modi cannot afford to anger ahead of general elections due by May.

The farmers have said they will march from 0530 GMT from the spot where authorities had stopped them by erecting barricades on the border of Punjab state with Haryana, about 200 km (125 miles) north of Delhi, blocking a highway.

“It is not right that such massive barricades have been placed to stop us,” said one of the farmers’ leaders, Jagjit Singh Dallewal. “We want to march to Delhi peacefully. If not, they should accede to our demands.”

Police in riot gear lined both sides of the heavily barricaded highway, as the farmers, gathering amid morning fog, waved colourful flags emblazoned with the symbols of their unions, while loudspeakers urged them to fight for their rights.

Television images showed some wearing gas masks to counter tear gas police have used in the past to try and disperse the protesters.

Late on Tuesday, Haryana police’s chief ordered the immediate seizure of the heavy equipment brought by the farmers, to prevent its use by protesters in destroying barricades.

Police also asked owners of such equipment not to lend or rent it to protesters, as its use to harm security forces would be a criminal offence.

Sunday’s government proposal of minimum support prices to farmers who diversify their crops to grow cotton, pigeon peas, black matpe, red lentils and corn was rejected by the protesters, who wanted additional foodgrains covered.

Agriculture Minister Arjun Munda urged the farmers to maintain the peace and rely on government talks to resolve their grievances.

“Through conversation, a solution will surely come out,” he told news agency ANI, in which Reuters has a minority stake.

Similar protests two years ago, when farmers camped for two months at the border of New Delhi, forced Modi’s government to repeal a set of farm laws.