New Delhi: Admitting that delay in land acquisition in Kerala for national highway projects have slowed down road building in the state, Union minister Mansukh L Mandaviya on Monday sought the cooperation of the state government in this regard.

The minister of state for road transport and highways said in the Rajya Sabha that land acquisition has been a problem there as population density was higher in the state.

"Land acquisition is a problem in Kerala" but the Centre has held talks with the state and is taking the matter forward, he said during the Question Hour.

"The ministry has approved 514 km length of state roads as new national highways in Kerala are subject to the outcome of the detailed project reports (DPR) and initiatives have been taken for preparation of the said DPRs," he said.

Mandaviya said the National Highways Authority of India planned to build 479 km of highways in the state but land acquisition was not there in place.