United States Ambassador to India David C Mulford, who played a key role in negotiations on civil nuclear deal, has been honoured with a prestigious American award for pushing relations between the two countries.

The Sue M Cobb Award of the State Department was bestowed on him in Washington on Monday, the US Embassy said.

US President George W Bush [Images] wrote a special letter of thanks to Mulford. "Under your leadership, we have seen the partnership between the United States and India strengthen and expand on a range of global issues," Bush said in the letter.

The award is given to a non-career Ambassador who has used private sector leadership and management skills to make a significant impact in carrying out the US foreign policy through pro-active diplomacy, the Embassy statement said.

Mulford has played a crucial role in the negotiations on Indo-US nuclear deal, which is seen as the most important single initiative between the two countries ever.

But, with political parties opposing operationalisation of the deal that was concluded in August, the envoy has lately been reaching out to leaders of main opposition party BJP to persuade them to give up their resistance.

He has met Leader of Opposition L K Advani, BJP president Rajnath Singh and former external affairs ministers Yashwant Sinha and Jaswant Singh to assuage their concerns over the agreement.