Scottish ministers are coming under pressure from an SNP-led committee of MSPs to end their repeated failure to meet climate targets by making major cuts in pollution from farming, housing and transport.

Farmers need to reduce their use of polluting chemical fertilisers, householders should be helped to better insulate old and leaky homes, and motorists should be persuaded to opt for cleaner electric and hybrid cars, MSPs say.

In a sharply worded ­submission this weekend, the Scottish Parliament's environment committee is urging ministers to ensure their climate reforms "are not just words". Scotland must not abandon, or water down, its world-leading ambitions to combat climate change, the committee says.

The Scottish Government has so far missed every statutory annual target to reduce carbon emissions in 2010, 2011 and 2012. This is a "disappointment", the committee says, and leaves ministers facing "significant difficulties" in meeting future targets.

Ministers have suggested lowering the climate targets to make meeting them easier. But this has been roundly rejected by MSPs on the committee as it "would send the wrong global message".

The intervention from the Rural Affairs, Climate Change and Environment Committee (RACCE) comes on the eve of the latest global climate summit, which opens in Lima, Peru, tomorrow. The new Scottish Climate Change Minister, Aileen McLeod, is expected to attend.

The committee's convener, SNP MSP Rob Gibson, has ­written McLeod a seven-page letter, which has been seen by the Sunday Herald. It calls for "urgent action" in response to the missed targets.

"The committee is concerned about the cumulative negative impact of the missed annual targets and would therefore like to see increased efforts across all sectors and parts of society in Scotland to make every effort possible to try and achieve each annual target," the letter says.

The failure of the agricultural sector to take up measures to cut carbon emissions such as reducing fertiliser use needs to be "urgently addressed", say the MSPs, who argue that if voluntary measures are shown not to work, mandatory moves should be considered.

McLeod is also asked to outline the action she is going to take to lower the energy wasted by "hard to heat and hard to treat" homes, and to combat rural and fuel poverty. On transport, the committee wants action to boost the use of electric cars by standardising charging points.

Gibson said: "We need to ensure phrases such as 'all ministers are climate change ministers' and 'all committees are climate change committees' are not just words and that responsibilities are understood and taken seriously."

The committee's move was welcomed by Stop Climate Chaos Scotland, which brings together 60 environment, faith, development and other groups. "The Scottish Government needs to come forward with an updated plan to compensate for the three missed targets and hit future ones," said the coalition's chairman, Tom Ballantine.

"It is vital that Scotland sends a positive message to the international community by delivering on our climate legislation. Scotland's emissions need to reduce year on year, in line with our Climate Act."

The Scottish Conservative MEP, Ian Duncan, who will be at the Lima climate summit, said Scotland's targets were meaningless if they remained unmet. "How do we encourage others countries at the conference to take action, when Scotland has missed every climate change target set?" he asked.

McLeod said a new Cabinet sub-committee on climate change had been set up to focus on delivering emissions reductions. She said: "Solid progress has been made towards achieving the 42% reduction in emissions by 2020 from a 1990 baseline, and this has been praised by our independent assessors."

"Our targets are world-leading and are not easy - but they are at the level the international community needs to match if the new climate treaty in Paris next year is to stand a good chance of limiting global temperature rise to no more than 2ºC."